Transponder chip module with coupling frame on a common substrate for secure and non-secure smartcards and tags

ABSTRACT

A capacitive coupling enhanced (CCE) transponder chip module (TCM) comprises an RFID chip (CM, IC), optionally contact pads (CP), a module antenna (MA), and a coupling frame (CF), all on a common substrate or module tape (MT). The coupling frame (CF,  320 A) may be in the form of a ring, having an inner edge (IE), an outer edge IE,  324 ) and a central opening (OP), disposed closely adjacent to and surrounding the module antenna (MA). A slit (S) may extend from the inner edge (IE) to the outer edge (OE) of the coupling frame (CF) so that the coupling frame (CF) is “open loop”. An RFID device may comprise a transponder chip module (TCM) having a module antenna (MA), a device substrate (DS), and an antenna structure (AS) disposed on the device substrate (DS) and connected with the module antenna (MA). A portion of a conductive layer (CL,  904 ) remaining after etching a module antenna (MA) may be segmented to have several smaller isolated conductive structures.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from and is a continuation-in-part ornonprovisional filing of:

-   nonprovisional of U.S. 62/080,332 filed 16 Nov. 2014-   nonprovisional of U.S. 62/069,544 filed 28 Oct. 2014-   continuation-in-part of U.S. Ser. No. 14/523,993 filed 27 Oct. 2014-   nonprovisional of U.S. 62/061,689 filed 8 Oct. 2014-   continuation-in-part of U.S. Ser. No. 14/492,113 filed 22 Sep. 2014-   nonprovisional of U.S. 62/048,373 filed 10 Sep. 2014-   nonprovisional of U.S. 62/044,394 filed 1 Sep. 2014-   continuation-in-part of U.S. Ser. No. 14/465,815 filed 21 Aug. 2014-   nonprovisional of U.S. 62/039,562 filed 20 Aug. 2014-   continuation-in-part of U.S. Ser. No. 14/281,876 filed 19 May 2014    (US 20140284386, 25 Sep. 2014)-   continuation-in-part of U.S. Ser. No. 14/225,570 filed 26 Mar. 2014    (US 20140209691, 31 Jul. 2014)-   continuation-in-part of U.S. Ser. No. 14/078,527 filed 13 Nov. 2013    (US 20140104133, 17 Apr. 2014)-   continuation-in-part of U.S. Ser. No. 14/020,884 filed 8 Sep. 2013    (US 20140091149, 3 Apr. 2014)-   continuation-in-part of U.S. Ser. No. 13/600,140 filed 30 Aug. 2012    (US 20130075477, 28 Mar. 2013)-   continuation-in-part of U.S. Ser. No. 14/259,187 filed 23 Apr. 2014    (US20140284387, 25 Sep. 2014) which is a continuation of    -   U.S. Ser. No. 13/931,828 filed 29 Jun. 2013 (U.S. Pat. No.        8,708,240, 29 Apr. 2014) which is a continuation of        -   U.S. Ser. No. 13/205,600 filed 8 Aug. 2011 (U.S. Pat. No.            8,474,726, 2 Jul. 2013)-   continuation-in-part of U.S. Ser. No. 13/730,811 filed 28 Dec. 2012    (US 20140024732, 16 Jan. 2014), which is a continuation-in-part of    U.S. Ser. No. 13/310,718 filed 3 Dec. 2011 (U.S. Pat. No. 8,366,009,    5 Feb. 2013)

TECHNICAL FIELD

The disclosure relates to RFID devices including “secure documents” or“RFID tags” such as electronic passports, electronic ID cards andsmartcards (or payment cards, electronic tickets, and the like), or chipcards having RFID (radio frequency identification) chips or chip modules(CM) capable of operating in a “contactless” mode (ISO 14443 or NFC/ISO15693) and, may also be applicable to dual interface (DI) smartcards andsecure documents which can also operate in a contact mode (ISO 7816-2).This may include “non-secure smartcards and tags” such as contactlessdevices in the form of keycards, building access cards, security badges,access control cards, asset tags, event passes, hotel keycards, wearabledevices, tokens, small form factor tags, data carriers and the likeoperating in close proximity with a contactless reader.

BACKGROUND

A dual interface (DI or DIF) smartcard (or smart card; SC) may generallycomprise:

-   -   an antenna module (AM) having a module antenna (MA) for        contactless operation and contact pads (CP) for contact        operation,    -   a card body (CB) having layers of plastic or metal, or        combinations thereof, and    -   a booster antenna (BA) disposed in the card body (or “inlay”).        Some examples of smart cards having booster antennas are        disclosed in U.S. Ser. No. 14/020,884 filed 8 Sep. 2013 (US        20140091149, 3 Apr. 2014)

The antenna module (AM), which may be referred to as a transponder chipmodule (TCM) or RFID module may generally comprise:

-   -   a module tape (MT) or chip carrier tape (CCT), more generally,        simply a “substrate”;    -   a contact pad array (CPA) comprising 6 or 8 contact pads (CP, or        “ISO pads”) disposed on a “face up side” or “contact side” (or        surface) of the module tape (MT), for interfacing with a contact        reader in a contact mode (ISO 7816);    -   an RFID chip (CM, IC) which may be a bare, unpackaged silicon        die or a chip module (a die with leadframe, interposer, carrier        or the like) disposed on a “face down side” or “bond side” or        “chip side” (or surface) of the module tape (MT);    -   a module antenna (MA) or antenna structure (AS) disposed on the        face down side of the module tape (MT) for implementing a        contactless interface, such as ISO 14443 and NFC/ISO 15693 with        a contactless reader or other RFID device.

An antenna modules (AM) which may be able to operate without a boosterantenna (BA) in the card body (CB) may be referred to as transponderchip modules (TCM), or as a transponder IC module.

The antenna module (AM) or transponder chip module (TCM) may begenerally rectangular, having four sides, and measuring approximately8.2 mm×10.8 mm for a 6-contact module and 11.8 mm×13.0 mm for an8-contact module. Alternatively, the transponder chip module (TCM) maybe round, elliptical, or other non-rectangular shape. When operating ina contactless mode, the antenna module (AM) or transponder chip module(TCM) may be powered by RF from an external RFID reader, and may alsocommunicate by RF with the external RFID reader.

A module antenna (MA) may be disposed on the module tape (MT) forimplementing a contactless interface, such as ISO 14443 and NFC/ISO15693. Contact pads (CP) may be disposed on the module tape (MT) forimplementing a contact interface, such as ISO 7816. The contact pads(CP) may or may not be perforated. The module tape (MT) may comprise apattern of interconnects (conductive traces and pads) to which the RFIDchip (CM, IC) and contact pads (CP) may be connected. The module tape(MT) may be “single-sided”, having a conductive layer (or cladding, orfoil) on only one side thereof, such as the “face-up” side thereof, suchas for the contact pads (CP). The module tape (MT) may be“double-sided”, having conductive layers (or claddings, or foils) onboth sides thereof. A conductive layer on the “face-down” side of themodule tape (MT) may be etched to form a module antenna (MA) having anumber of tracks (traces) separated by spaces.

The module antenna (MA) may be wire-wound, or etched, for example:

-   -   The module antenna (MA) may comprise several turns of wire, such        as 50 μm diameter insulated wire. Reference may be made to U.S.        Pat. No. 6,378,774 (2002, Toppan), for example FIGS. 12A, B        thereof.    -   The module antenna (MA) may be a chemically-etched planar        antenna (PA) structure. Reference may be made to U.S. Pat. No.        8,100,337 (2012, SPS), for example FIG. 3 thereof.    -   The module antenna (MA) may comprise a laser-etched planar        antenna (PA) structure (LES). Reference may be made to U.S. Ser.        No. 14/281,876 filed 19 May 2014 (US 20140284386, 25 Sep. 2014),        incorporated by reference herein.

A planar antenna (PA) structure, or simply “planar antenna (PA)”,whether chemically-etched (CES) or laser-etched (LES) may comprise along conductive trace or track having two ends, in the form of a planarspiral encircling the RFID chip on the face-down side of the moduletape. This will result in a number of tracks (actually, one longspiraling track), separated by spaces. The track width may beapproximately 100 μm. Generally, with laser etching, the track width andthe spacing between tracks can be made smaller than with chemicaletching, and the tracks themselves can be made narrower than withchemical etching.

The (two) ends of the module antenna (MA) may be connected, eitherdirectly or indirectly to corresponding terminals (LA, LB) of the RFIDchip (IC, CM). For example, one or both ends of the module antenna (MA)may be connected to bond pads or interconnect traces on the face-downside of the module tape (MT), to which the terminals of the RFID chip(IC, CM) may also be connected.

Alternatively, one or both ends of the module antenna (MA) may beconnected via electrically conductive structures, which may be referredto as “contact bridges” or “connection bridges”, disposed on the face-upside of the module tape (MT), and which may be formed from the sameconductive layer as the contact pads (CP). Some examples of connectionbridges may be found in

-   -   US 20130146670 (2013 Jun. 13, Grieshofer et al; “Infineon”)    -   commonly-owned, copending U.S. Ser. No. 14/523,993 filed 27 Oct.        2014

The antenna (or antenna structure AS) may be laser etched from a copperlayer (cladding or foil), which may have a thickness of approximately 18μm-35 μm, but may be approximately 12 μm, which may be less than theskin depth of copper (18 μm), forming a number of tracks separated by adistance approximately equal to the width of the laser beam, such asapproximately 25 μm. Subsequent to laser etching, the antenna structuremay be plated, which may reduce the distance between tracks toapproximately 20 μm (for example). This may result in increasedperformance of the antenna structure, and the overall antenna module AM(or transponder chip module (TCM)), and reduce performance constraintson the performance of a booster antenna (BA) in the card body (CB) ofthe smartcard (SC).

A module antenna (MA) connected to an RFID chip (CM), typically on asubstrate or module tape (MT), may be referred to as a “transponder”.Generally, such a transponder may be a “passive” transponder which doesnot have its own power source (e.g., battery), but rather which receives(harvests) its operating power from an external reader (interrogator)rather, for example, from a battery. An “active transponder” may haveits own internal power source, such as a battery.

Transponder chip modules (TCM) which are passive transponders may havean “activation distance” which may refer to the distance from anexternal reader at which the transponder may commence operation (turnon), and may also have a “read/write” distance which may refer to thedistance from an external reader at which the transponder maycommunicate effectively and reliably, in both directions, with thereader.

Activation and read/write distances of at least a few centimeters (cm)are desirable. However, conventional antenna modules (AM) may require abooster antenna (BA) in a card body (CB) to achieve these distances. Thetransponder chip modules (TCM) disclosed herein may be capable ofgreater activation and read/write distances, without requiring a boosterantenna (BA).

Some terms which may be used herein may include:

-   -   “skin depth” relates to the “skin effect” which is the tendency        of an alternating electric current (AC) to become distributed        within a conductor such that the current density is largest near        the surface of the conductor. A “skin depth”, or minimum        thickness for conducting current may be defined, for a given        material at a given frequency. For example, at 13.56 MHz, the        skin depth for copper may be approximately 18 μm (17.7047 μm).    -   “transparency” refers to the ability of electromagnetic        radiation to pass through a material. A threshold for        non-transparency (or the ability to interact with RF) may be a        fraction of the skin depth for the metal layer in question at a        given frequency of interest. For example, the non-transparency        threshold for copper at 13.56 MHz, may be one-tenth of the skin        depth, or approximately 1.7 μm.

SUMMARY

It is a general object of the invention to provide improved techniquesfor improving coupling of smartcards (as an example of secure documents,and the like) with a contactless reader. This may be of particularinterest in the milieu of metallized (or metal) smartcards.

According to the invention, generally, a coupling frame (CF) may beincorporated into an antenna module (AM) or transponder chip module(TCM) on one or both sides of the module tape (MT) or chip carrier tape(CCT) of the transponder chip module (TCM). One or more module antennas(MA) or planar antennas (PA) may be incorporated into the transponderchip module (TCM). The module tape (MT) with module antenna (MA) andcoupling frame (CF) may be considered to be an interim product. An RFIDchip (CM, IC) may be mounted to an area on a surface of the module tape(MT), and connected to the module antenna (MA).

The coupling frame (CF) may be formed from a conductive metal layer (ML)on a surface of the module tape (MT), which may be the selfsame metallayer (ML) used to form the contact pads (CP) on the face-up surface ofthe module tape (MT), or which is used to form bond pads andinterconnect traces on the face-down side of the module tape (MT).

The coupling frame (CF) may be in the form of a ring (such as arectangular ring) having an opening (OP) defined by an inner edge (IE)thereof. A slit (S) may extend from the opening (OP) of the couplingframe (CF) to an outer edge (OE) thereof. The coupling fame (CF) may bedisposed on a module tape (MT) so that its opening (OP) is disposed“closely adjacent” to and “partially surrounding” a module antenna (MA)of a transponder chip module (TCM).

-   -   As used herein, “closely adjacent” may typically mean that the        inner edge (IE) of the coupling frame (CF) is separated by only        a small gap (such as less than 100 μm) from an outer turn of the        module antenna (MA), which may generally be true when the        coupling frame (CF) is on the same side of the module tape (MT)        as the module antenna (MA), and “substantially coplanar”        therewith. However, in some embodiments, the coupling frame (CF)        may be on an opposite side of the module tape (MT) from the        module antenna (MA), and an inner portion of the coupling frame        (CF) may overlap (be above) an outer portion of the module        antenna (MA). This latter situation (overlapping) is intended to        be included in the definition of “closely adjacent”, and in a        definition of “substantially coplanar” therewith.    -   As used herein, “partially surrounding” may typically mean that        the inner edge (IE) of the coupling frame (CF) almost nearly        encircles (except for the slit S) the module antenna (MA), which        may generally be true when the coupling frame (CF) is on the        same side of the module tape (MT) as the module antenna (MA),        and substantially coplanar therewith. However, in some        embodiments, the coupling frame (CF) may be on an opposite side        of the module tape (MT) from the module antenna (MA), with an        inner portion of the coupling frame (CF) overlapping (disposed        above) an outer portion of the module antenna (MA), or even the        entire module antenna (MA). This latter situation (overlapping)        is intended to be included in the definition of “partially        surrounding”.

The module antenna (MA) which may be a planar antenna (PA), such as ametal layer etched to have tracks (traces) separated by spaces. Thecoupling frame (CF) ring may have an inner edge (IE) and an outer edge(OE). Both of the inner and outer edges may have the same geometric form(shape), such as rectangular. The inner edge may have a geometric form(such as rectangular) corresponding to the geometric form of the moduleantenna (MA), and an outer edge with another geometric form (such asround or elliptical). The coupling frame (CF) may be surround at leasttwo sides of the module antenna (MA), such as three sides thereof, orall four sides. In the case of the coupling frame (CF) surroundingsubstantially the entire planar module antenna (MA), a slit (S, or slot,or gap) may be provided, extending from the inner edge (IE) to the outeredge (OE) of the coupling frame (CF) so that it is an open-loopconductor, having two ends and a gap therebetween. When the term“partially surrounding” is used herein, it generally may refer to such acoupling frame (CF) which substantially surrounds (except for the slit,slot or gap) the planar antenna (PA) structure. In some instances, thecoupling frame (CF) may be described simply as “surrounding” the moduleantenna (MA), it being understood that there is a slit (S) extendingfrom the outer edge (OE) of the coupling frame (CF) to the inner edge(IE) thereof.

According to some embodiments (examples) of the invention, generally aconductive layer (CL) may be formed as coupling frame (CF) having anouter edge (OE) and an inner edge (IE defining an opening (OP) and maybe disposed with its opening (OP) surrounding and closely adjacent atransponder chip module (TCM), particularly the module antenna (MA)thereof, and may be substantially coplanar with the module antenna (MA).The coupling frame (CF) may have a discontinuity, comprising a slit (S)or a non-conductive stripe (NCS), in the metal layer (ML), extendingfrom its inner edge (IE) (which defines the opening (OP)) to an outeredge (OE) thereof, whereby the metal layer (ML) comprises an open-loopcoupling frame (CF) having two ends. For example, the coupling frame(CF) may be “C-shaped”.

Some embodiments of the invention(s) disclosed herein may relate totransponder chip modules (TCMs) with integrated coupling frame (CF) forimplanting, insertion or placement in secure documents, such as in or oninlay substrates or smartcard stack-ups.

Some embodiments of the invention(s) disclosed herein may relate to thearrangement of contact pads or isolated metal features such as a logo onone side of a chip carrier tape (CCT) and a planar antenna (PA)structure (laser etched antenna structure (LES) or chemical-etchedantenna structure (CES)) on an opposite side of the chip carrier tape(CCT) which forms a transponder chip module (TCM) when connected to anRFID chip, and the arrangement of a coupling frame (CF) on one or bothsides of the chip carrier tape (CCT) and partially surrounding theplanar antenna (PA) to enhance the read/write distance whencommunicating at close proximity with a contactless reader.

Some embodiments of the invention(s) disclosed herein may relate to achip carrier tape (CCT) having a single metal layer (ML) disposed on asuitable substrate such as glass-reinforced epoxy, Kapton, PET or thelike with said metal layer (ML) prepared with isolated metal features(such as, but not limited to, contact pads (CP), connection bridges(CBR) and decorative features, logos and the like), a planar antenna(PA) structure, connection pads (CP), and a coupling frame (CF) onsubstantially the same plane, to accept an RFID chip for die and wirebonding or flip chip assembly.

Some embodiments of the invention(s) disclosed herein may relate to achip carrier tape (CCT) having at least two metal layers, one disposedon top (face-up side) and the other on bottom (face-down side) of asuitable substrate such as double-sided glass epoxy tape or the like,with the face-up side prepared with isolated metal features, connectionbridge(s) with or without a coupling frame (CF), and a planar antennastructure with connection pads and coupling frame (CF) prepared on theface-down side of the chip carrier tape (CCT), to accept an RFID chipfor die and wire bonding or flip chip assembly.

Some embodiments of the invention(s) disclosed herein may relate to acoupling frame (CF) partially surrounding a planar antenna (PA)structure on a chip carrier tape (CCT) with a slit (or slot, or gap)extending from an inner edge of the coupling frame (CF) to an outer edgethereof to create an open-circuit conductive ring around the area of theplanar antenna (PA) structure. The slit may be straight extendingradially from the inner edge to the outer edge, or extending at an anglefrom the inner to the outer edge, or may have an artist characteristic(such as a zig-zag slit or a slit which is becomes wider or narrow alongits length). Multiple slits may be provided in a single coupling frame(CF). Multiple coupling frames, each having slits may be provided.

Some embodiments of the invention(s) disclosed herein may relate to aflexible chip carrier tape (CCT), having a single or double-sidedmetallization layer in standard super 35 mm format or any suitableformat. The metallization layer or layers can be electrodepositedcopper, rolled annealed copper, plated copper, selectively plated copperor any suitable conductive medium. The planar antenna (PA) may bearranged slightly smaller than the footprint of a six or eight contactmodule or the planar antenna may be arranged substantially larger,taking advantage of the space on a 35 mm tape or any suitable substrate.

Some embodiments of the invention(s) disclosed herein may relate to atransponder chip module (TCM) partially surrounded by a coupling frame(CF) on one or both sides of a double-sided chip carrier tape (CCT),with design features (artwork) on one side (face-up side) and a planarantenna (PA) with connection pads on the opposite side (face-down side),with a gap between the planar antenna (PA) and coupling frame (CF)ranging from the width of a laser beam (such as 25 μm), or less, to theconventional feature size in a chemical etch process, e.g. 100 μm, ormore.

Some embodiments of the invention(s) disclosed herein may relate to atransponder chip module (TCM) partially surrounded by a coupling frame(CF) on a common chip carrier tape whereby the read/write performance ofthe device is primarily determined by: the dimensions and thickness ofthe isolated metal features (such as contact pads CP) on the face-upside of the chip carrier tape (CCT), in particular the gap between saidfeatures, typically 200 μm; the surface area of the planar antenna (PA)on the face-down side of the chip carrier tape (size and shape of theantenna, thickness of the metal layer (ML), spacing between tracks,width of the tracks, number of turns); the surface area of the couplingframe (CF) partially surrounding the planar antenna (PA) of thetransponder chip module (TCM); the dimensional gap between the planarantenna (PA) and the coupling frame (CF); the dimensional slit or slotin the coupling frame (CF); and RFID chip, in particular the inputcapacitance, typically 17 pF or 69 pF.

Some embodiments of the invention(s) disclosed herein may relate to atransponder chip module (TCM) partially surrounded by a coupling frame(CF) on a common chip carrier tape and mounted to an inlay substratewhich may be laminated or attached to additional substrate layer orlayers to create a data-page or an e-cover in an electronic passportbooklet.

Some embodiments of the invention(s) disclosed herein may relate to atransponder chip module (TCM) partially surrounded by a coupling frame(CF) on a common chip carrier tape and mounted to an inlay substratewhich may be laminated to additional substrate layers to create acontactless card. A transparent window in the substrate layers may allowfor the isolated metal features on the top side of the transponder chipmodule to be visible.

Some embodiments of the invention(s) disclosed herein may relate to atransponder chip module (TCM) partially surrounded by a coupling frame(CF) on a common chip carrier tape, punched from a super 35 mm tape andimplanted in a card body to create a dual interface smartcard.

In some of the embodiments described herein, the substrate forsupporting the coupling frame (CF) could be a rigid insulated substratein which a conductive metal layer (ML) is deposited on the surface. Themetal layer (ML) could be laser etched to expose the slit (S). Themodule antenna (MA) could be formed on the same substrate or on aseparate substrate.

An antenna module (AM) or transponder chip module (TCM) may comprise anopen loop coupling frame (CF) surrounding, disposed on the module tape(MT) or chip carrier tape (CCT) closely adjacent to, and substantiallycoplanar with (including overlapping, including on the same or anotherside of the module tape (MT)) from a module antenna (MA) or planarantenna (PA), or simply antenna structure (AS), connected to an RFIDchip (IC, CM).

A capacitive coupling enhanced (CCE) transponder chip module (TCM) maycomprise an RFID chip (CM, IC), optionally contact pads (CP), a moduleantenna (MA), and a coupling frame (CF), all on a common substrate ormodule tape (MT). The coupling frame (CF) may be in the form of a ring,having a central opening (OP) defined by an inner edge (IE) thereof, anouter edge IE, and a slit (S) extending from the inner edge (IE) to theouter edge (OE) of the coupling frame (CF) so that the coupling frame(CF) is “open loop”. The coupling frame may be disposed with its inneredge (IE) closely adjacent to and surrounding a module antenna (MA)structure of the transponder chip module (TCM). An RFID device maycomprise a transponder chip module (TCM) having a module antenna (MA), adevice substrate (DS), and an antenna structure (AS) disposed on thedevice substrate (DS) and connected with the module antenna (MA). Aportion of a conductive layer (CL, 904) remaining after etching a moduleantenna (MA, 900) may be segmented to have several smaller isolatedconductive structures (904 b,c,d).

According to some embodiments (examples) of the invention, a capacitivecoupling enhanced (CCE) transponder chip module (TCM) may comprise: amodule tape (MT); an area for mounting an RFID chip (IC) on the moduletape (MT); and a module antenna (MA, PA) disposed on the module tape(MT); and may be characterized by: a conductive coupling frame (CF)disposed on the module tape (MT) having an opening (OP) defined by aninner edge (IE), an outer edge (OE) and a discontinuity comprising aslit (S) or a non-conductive stripe (NCS) extending from the opening(OP) to the outer edge (OE); wherein the opening (OP) is disposedsurrounding and closely adjacent to the module antenna (MA).

The coupling frame (CF) may be disposed on the same side of the moduletape (MT) as the module antenna (MA, PA). The coupling frame (CF) may bedisposed on an opposite side of the module tape (MT) from the moduleantenna (MA, PA). The coupling frame (CF) may be formed from aconductive layer (CL) on the module tape (MT) which is one of the (i)conductive layer used to form contact pads (CP) on the face-up side ofthe module tape (MT) and (ii) the conductive layer used to form themodule antenna on the face-down side of the module tape (MT). Thecoupling frame (CF) may comprise wire (EW) embedded in the module tape(MT).

The module antenna (MA) may comprise an etched planar antenna (PA)having a number of tracks (traces) separated by spaces; wherein: a trackwidth is less than 100 μm; and a spacing between adjacent tracks is lessthan 75 μm. The module antenna (MA) may comprise two antenna structures(PA-1, PA-2). A capacitor (CAP) may be connected with the module antenna(MA).

Two coupling frames (CF-1, CF-2) may be disposed on the module tape(MT)—one disposed on a face-up side of the module tape (MT) the otherdisposed on a face-down side of the module tape (MT). The coupling frame(CF) may be disposed around the module antenna (MA) with its opening(OP) surrounding the module antenna (MA) and closely adjacent thereto.The coupling frame (CF) may overlap at least a portion of the moduleantenna (MA). The coupling frame (CF) may extend a few millimetersbeyond the module antenna (MA) on one side thereof, and extends a fewcentimeters beyond the module antenna (MA) on an opposite side thereof.The coupling frame (CF) may have a geometry defined by a shape of itsouter edge (OE) which is different than a geometry of the transponderchip module (TCM).

A plating line (PL) may extend from outside of the coupling frame (CF),through the slit (S) in the coupling frame (CF) to the module antenna(MA). Conductive traces (CT) may extend between at least some contactpads (CP) and connection bridges (CBR) of the contact pad array (CPA).

According to some embodiments (examples) of the invention, a capacitivecoupling enhanced transponder chip module (CCE-TCM) may comprise: amodule tape (MT); an RFID chip (IC) disposed on the module tape (MT); anetched planar antenna (PA) disposed on the module tape (MT); and acoupling frame (CF) disposed on the module tape (MT), closely adjacentto the module antenna (MA), having an opening (OP) aligned with themodule antenna (MA) and a slit (S) extending from the opening (OP) to anouter edge (OE) of the coupling frame (CF) so that the coupling frame(CF) is an open loop.

The capacitive coupling enhanced transponder chip module (CCE-TCM) mayfurther comprise:

contact pads (CP) so that the capacitive coupling enhanced transponderchip module (CCE-TCM) can function with dual interfaces (contactless andcontact).

According to some embodiments (examples) of the invention, a method ofimproving coupling between a transponder chip module (TCM) and anexternal reader, the transponder chip module (TCM) comprising an RFICchip (IC, 404) and a module antenna (MA), may be characterized by:incorporating an open-loop coupling frame (CF) in the transponder chipmodule (TCM).

The coupling frame (CF) may be disposed surrounding and closely adjacentto the module antenna (MA). The coupling frame (CF) may have an opening(OP); and a slit (S) may extend from the opening (OP) to an outer edge(OE) of the coupling frame (CF)

According to some embodiments (examples) of the invention, a transponderdevice (TD) may comprise: a device substrate (DS); a transponder chipmodule (TCM) comprising an RFID chip (IC), with a module antenna (MA)disposed on a carrier substrate (CS); and an antenna structure (AS)disposed on the device substrate (DS) and connected with the transponderchip module (TCM).

According to some embodiments (examples) of the invention, a method offorming a module antenna (MA) for a transponder chip module (TCM) maycomprise: etching a module antenna (MA) from a conductive layer (CL) ona module tape to have tracks separated by spaces; and segmenting aportion of the conductive layer (CL) remaining in an area inside of themodule antenna (MA) to comprise a plurality of small isolated conductivestructures rather than a single large conductive structure. The etchingstep may comprise laser etching.

The contact pads (CP), coupling frame (CF) and antenna structures (AS)described herein may be formed using laser etching (isolation technique)of copper cladded “seed” layers on a module tape MT using a UVnanosecond or picosecond laser.

In the main, the antenna modules (AM) and transponder chip modules (TCM)disclosed herein may be described in the context of RFID applications,especially payment. Some of the concepts disclosed herein may beapplicable to memory devices in combination with RFID. For example,rather than having ISO contact pads (ISO 7816), such a module may beprovided with USB (Universal Serial Bus) format contact pads. Thecontact pads could in essence be USB contact pads. Such an RFID devicehaving a contactless interface and a contact interface implemented inUSB format may constitute an RFID/USB tag.

In their various embodiments, the invention(s) described herein mayrelate to industrial and commercial industries, such RFID applications,payment smartcards, electronic passports, identity cards, access controlcards, wearable devices the like.

Other objects, features and advantages of the invention(s) disclosedherein may become apparent in light of the following illustrations anddescriptions thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference will be made in detail to embodiments of the disclosure,non-limiting examples of which may be illustrated in the accompanyingdrawing figures (FIGs). The figures may generally be in the form ofdiagrams. Some elements in the figures may be exaggerated, others may beomitted, for illustrative clarity. Some figures may be in the form ofdiagrams.

Although the invention is generally described in the context of variousexemplary embodiments, it should be understood that it is not intendedto limit the invention to these particular embodiments, and individualfeatures of various embodiments may be combined with one another. Anytext (legends, notes, reference numerals and the like) appearing on thedrawings are incorporated by reference herein.

Some elements may be referred to with letters (“AM”, “BA”, “CB”, “CCM”,“CM”, “MA”, “MT”, “PA”, “TCM”, etc.) rather than or in addition tonumerals. Some similar (including substantially identical) elements invarious embodiments may be similarly numbered, with a given numeral suchas “310”, followed by different letters such as “A”, “B”, “C”, etc.(resulting in “310A”, “310B”, “310C”), and variations thereof, and maycollectively (all of them at once) referred to simply by the numeral(“310”).

FIG. 1 is a diagram, in cross-section, of a dual-interface smart card(SC) and readers.

FIG. 1A is a diagram showing the ISO-7816 specification for contact padlayout.

FIG. 1B is a diagram (plan view) of an 8-pad pattern for ISO-7816contacts.

FIG. 1C is a diagram (plan view) of a 6-pad pattern for ISO-7816contacts.

FIG. 1D is a diagram (plan view) of a smart card (SC).

FIG. 2A is a diagram (cross-sectional view) of an antenna module (AM).

FIG. 2B is a diagram (plan view) of a contact side of a dual-interfaceantenna module (AM).

FIG. 3A is a plan view of a capacitive coupling enhanced (CCE)transponder chip module (TCM) which has a coupling frame (CF)incorporated on its module tape (MT).

FIGS. 3A-1, 3A-2 are detailed views of the ends the coupling frame (CF)shown in FIG. 3A.

FIG. 3B is a plan view of a capacitive coupling enhanced (CCE)transponder chip module (TCM) which has a coupling frame (CF)incorporated on its module tape (MT).

FIG. 3C is a diagram (cross-sectional views) of a capacitive couplingenhanced (CCE) transponder chip module (TCM).

FIGS. 3D-3I are diagram (plan views) of capacitive coupling enhanced(CCE) transponder chip modules (TCM).

FIG. 3I is a diagram (plan view) of a capacitive coupling enhanced (CCE)transponder chip module (TCM), as it may be positioned in a smart card(SC).

FIGS. 3J,K,L,M are diagrams (cross-sectional views) of capacitivecoupling enhanced (CCE) transponder chip modules (TCM).

FIG. 3N is a diagram (plan view) of a capacitive coupling enhanced (CCE)transponder chip module (TCM), as it may be positioned in a smart card(SC).

FIG. 3O is a diagram showing a contact pad array (CPA) having aconductive trace extending between the contact pads (CP) thereof.

FIG. 4A is a diagram (plan view) of a capacitive coupling enhanced (CCE)transponder chip module (TCM) which has a coupling frame (CF)incorporated on its module tape (MT) or chip carrier tape (CCT).

FIG. 4B is a diagram (cross-sectional view) of the capacitive couplingenhanced (CCE) transponder chip module (TCM) of FIG. 4A.

FIG. 5A is a plan view of a capacitive coupling enhanced (CCE)transponder chip module (TCM) which has a coupling frame (CF)incorporated on its module tape (MT) or chip carrier tape (CCT).

FIG. 5B is a plan view of a capacitive coupling enhanced (CCE)transponder chip module (TCM) which has a coupling frame (CF)incorporated on its module tape (MT) or chip carrier tape (CCT).

FIG. 6A is a plan view of a smartcard (SC) having a coupling frame (CF)formed by embedding wire (in the manner of a booster antenna BA).

FIG. 6B is a plan view of a smartcard (SC) having a coupling frame (CF)formed by embedding wire (in the manner of a booster antenna BA).

FIG. 6C is a diagram (plan view) of a coupling frame (CF) with couplercoil (CC) disposed in a card body (CB) of a smart card (SC).

FIG. 6D is a cross-sectional view of the smart card (SC) with couplingframe (CF) of FIG. 6C, taken on a line 6D-6D through FIG. 6C.

FIG. 6E is a plan view of a card body (CB) of a smart card (SC)comprising a coupling frame (CF) having a slit (S) and also having oneor more coupler coils (CC) formed therein.

FIG. 6F is a plan view of a module tape (MT) of a capacitive couplingenhanced (CCE) transponder chip module (TCM) comprising a coupling frame(CF) having a slit (S) and also having one or more coupler coils (CC)formed therein.

FIG. 7 is a diagram (perspective view) showing a transponder device (TD)having an elongated (long and narrow) form factor, suitable to beincorporated into a wristband product.

FIG. 8A is a diagram (perspective view) and FIG. 8B is a diagram(partial cross-sectional view) of a transponder device (TD) having anelongated (long and narrow) form factor, suitable to be incorporatedinto a wristband product.

FIG. 9A is a diagram (plan view) of an antenna structure (AS) which maybe a module antenna (MA) which has been etched to have tracks (traces)separated by spaces, with a large area of conductive layer (CL)remaining within the antenna structure (AS).

FIGS. 9B, 9C, 9D are diagrams (plan view) of antenna structures (AS)which have been etched to have tracks (traces) separated by spaces, witha smaller, segmented areas of conductive layer (CL) remaining within theantenna structure (AS).

DESCRIPTION

Various embodiments (or examples) may be described to illustrateteachings of the invention(s), and should be construed as illustrativerather than limiting. It should be understood that it is not intended tolimit the invention(s) to these particular embodiments. It should beunderstood that some individual features of various embodiments may becombined in different ways than shown, with one another. Referenceherein to “one embodiment”, “an embodiment”, or similar formulations,may mean that a particular feature, structure, operation, orcharacteristic described in connection with the embodiment is includedin at least one embodiment of the present invention. Some embodimentsmay not be explicitly designated as such (“an embodiment”).

The embodiments and aspects thereof may be described and illustrated inconjunction with systems, devices and methods which are meant to beexemplary and illustrative, not limiting in scope. Specificconfigurations and details may be set forth in order to provide anunderstanding of the invention(s). However, it should be apparent to oneskilled in the art that the invention(s) may be practiced without someof the specific details being presented herein. Furthermore, somewell-known steps or components may be described only generally, or evenomitted, for the sake of illustrative clarity. Elements referred to inthe singular (e.g., “a widget”) may be interpreted to include thepossibility of plural instances of the element (e.g., “at least onewidget”), unless explicitly otherwise stated (e.g., “one and only onewidget”).

In the following descriptions, some specific details may be set forth inorder to provide an understanding of the invention(s) disclosed herein.It should be apparent to those skilled in the art that theseinvention(s) may be practiced without these specific details. Anydimensions and materials or processes set forth herein should beconsidered to be approximate and exemplary, unless otherwise indicated.Headings (typically underlined) may be provided as an aid to the reader,and should not be construed as limiting.

Reference may be made to disclosures of prior patents, publications andapplications. Some text and drawings from those sources may be presentedherein, but may be modified, edited or commented to blend more smoothlywith the disclosure of the present application.

In the main hereinafter, RFID cards, electronic tags and securedocuments in the form of pure contactless cards, dual interface cards,phone tags, electronic passports, national identity cards and electronicdriver licenses may be discussed as exemplary of various features andembodiments of the invention(s) disclosed herein. As will be evident,many features and embodiments may be applicable to (readily incorporatedin) other forms of smart cards, such as EMV payment cards, metalcomposite cards, metal hybrid cards, metal foil cards, access controlcards and secure credential documents. As used herein, any one of theterms “transponder”, “tag”, “smart card”, “data carrier”, “wearabledevice” and the like, may be interpreted to refer to any other of thedevices similar thereto which operate under ISO 14443 or similar RFIDstandard. The following standards are incorporated in their entirety byreference herein:

-   -   ISO/IEC 7810 is an ISO standard s an international standard that        defines the physical characteristics for identification cards.        The characteristics specified include: (i) physical        dimensions, (ii) resistance to bending, flame, chemicals,        temperature and humidity, and (iii) toxicity. The standard        includes test methods for resistance to heat. [2]    -   ISO/IEC 14443 (Identification cards—Contactless integrated        circuit cards—Proximity cards) is an international standard that        defines proximity cards used for identification, and the        transmission protocols for communicating with it.    -   ISO/IEC 15693 is an ISO standard for vicinity cards, i.e. cards        which can be read from a greater distance as compared to        proximity cards.    -   ISO/IEC 7816 is an international standard related to electronic        identification cards with contacts, especially smart cards.    -   EMV standards define the interaction at the physical,        electrical, data and application levels between IC cards and IC        card processing devices for financial transactions. There are        standards based on ISO/IEC 7816 for contact cards, and standards        based on ISO/IEC 14443 for contactless cards.

A typical transponder chip module (TCM) described herein may comprise

-   -   (i) a substrate, such as an epoxy-glass substrate, which may be        referred to as a module tape (MT) or a chip carrier tape (CCT)        and which may function as an inlay substrate;    -   (ii) an RFID chip (CM, IC) disposed on the substrate; and    -   (iii) a planar antenna (PA), or simply antenna structure (AS),        which may be a laser-etched antenna structure (LES) or a        chemically-etched antenna structure (CES) serving as a module        antenna (MA) for the transponder chip module (TCM).

A transponder chip module (TCM) may be referred to herein as an antennamodule (AM), and may have a wire-wound antenna structure (AS), ratherthan a planar antenna (PA).

As disclosed herein, a transponder chip module (TCM) may also comprise:

-   -   (iv) a coupling frame (CF) disposed on the substrate (MT) to        enhance coupling between the transponder chip module (TCM) and        the antenna of an external RFID “reader”, and may be referred to        as a “capacitive coupling enhanced” (CCE) transponder chip        module (TCM).

A capacitive-coupling enhanced (CCE) transponder chip module (TCM) maybe referred to herein simply as a transponder chip module (TCM), orsometimes as an antenna module (AM), but it should be evident from thecontext of the description(s) whether or not the transponder chip module(TCM) has a coupling frame (CF), and is indeed a capacitive-couplingenhanced (CCE) transponder chip module (TCM).

When “chip module” is referred to herein, it should be taken to include“chip”, and vice versa, unless explicitly otherwise stated. When“transponder chip module” (TCM) is referred to herein, it should betaken to include “antenna module” (AM), and vice versa, unlessexplicitly otherwise stated. The transponder chip module (TCM) may alsobe referred to as a “transponder IC module”. Throughout the variousembodiments disclosed herein, unless specifically noted otherwise (inother words, unless excluded), the element referred to as “CM” will mostappropriately be a bare integrated circuit (IC) die (or RFID chip),rather than a chip module (a die with a carrier). Some figures maypresent examples that are specifically “chip modules” having IC chips(such as a “CM”) mounted and connected to substrates. A “chip module”(die and carrier) with a planar (etched) antenna structure (PA, AS, LES,CES) and connected thereto may be referred to as a transponder chipmodule (TCM).

When “inlay substrate” is referred to herein, it should be taken toinclude “card body”, and vice versa, as well as any other substrate fora secure document, unless explicitly otherwise stated.

When “module tape” is referred to herein, it generally refers to amodule tape (MT) or chip carrier tape (CCT) comprising an epoxy-glasssubstrate having metallization (typically a copper layer) on one or bothsides thereof. The module tape (MT) may comprise insulating(electrically non-conductive) materials other than epoxy-glass, andprovides a substrate for supporting (and interconnecting) variouscomponents of the transponder chip module (TCM) with one another.

According to an aspect of the invention, generally, a coupling frame(CF) may be incorporated into an antenna module (AM) or transponder chipmodule (TCM) to enhance its read/write distance, and may be referred toas a capacitive coupling enhanced (CCE) transponder chip module (TCM). Acapacitive coupling enhanced (CCE) transponder chip module (TCM) mayoperate (function adequately) without a card body (CB) and without abooster antenna (BA). Again, throughout the descriptions set forthherein, a capacitive coupling enhanced (CCE) transponder chip module(TCM) may simply be referred to as a transponder chip module (TCM), forsake of brevity, the capacitive coupling enhanced feature being evidentby the presence of a coupling frame (CF) in the transponder chip module(TCM).

The transponder chip module (TCM) may comprise non-perforated isolatedmetal features such as contact pads (CP) on the face-up (contact) sideof the module tape (MT) and an RFID chip (CM, IC) and a planar (etched)antenna structure (AS, PA) on the face-down (chip or bond) side of themodule tape (MT). Some components and features on either side of themodule tape (MT), such as the contact pads (CP), bond pads and antennastructure (AS) may be laser-etched or chemically-etched. An antennaincorporated directly on the RFID chip may inductively couple with theplanar antenna structure (PA).

Throughout the various embodiments disclosed herein, unless specificallynoted otherwise (in other words, unless excluded), the element referredto as “CM” will most appropriately be a bare integrated circuit (IC) die(or RFID chip), rather than a chip module (a die with a carrier). Somefigures may present examples that are specifically “chip modules” havingIC chips (such as a “CM”) mounted and connected to substrates. A “chipmodule” (die and carrier) with a planar (etched) antenna structure (PA,AS, LES, CES) and connected thereto may be referred to as a transponderchip module (TCM).

When “inlay substrate” is referred to herein, it should be taken toinclude “card body”, and vice versa, as well as any other substrate fora secure document, unless explicitly otherwise stated.

When “module tape” is referred to herein, it generally refers to amodule tape (MT) or chip carrier tape (CCT) comprising an epoxy-glasssubstrate having metallization (typically a copper layer) on one or bothsides thereof.

Some of the descriptions that follow are in the context of dualinterface (DI, DIF) smart cards, but may relate mostly to thecontactless operation thereof. Many of the teachings set forth hereinmay be applicable to pure contactless cards, tags, wearables, securedocuments (e.g. electronic passports) and the like having only acontactless mode of operation. Some of the teachings set forth hereinmay be applicable to RFID devices, such as smart cards, which do nothave a booster antenna (BA).

Generally, any dimensions set forth herein are approximate, andmaterials set forth herein are intended to be exemplary. Conventionalabbreviations such as “cm” for centimeter, “mm” for millimeter, “μm” formicron, and “nm” for nanometer may be used.

Dual Interface (DI) Smart Card (SC) and Readers

FIG. 1 illustrates a smart card (SC) 100 in cross-section, along with acontact reader and a contactless reader. An antenna module AM (ortransponder chip module TCM) 110 may comprise a module tape (MT) 112, anRFID chip (CM, IC) 114 disposed on one side (face-down) of the moduletape (MT) along with a module antenna (MA) 116 and contact pads (CP) 118disposed on the other (face-up) side of the module tape (MT) forinterfacing with an external contact reader. The card body (CB) 120comprises a substrate (inlay substrate) which may have a recess (R) 122extending into one side thereof for receiving the antenna module (AM).The recess (R) may be stepped—such as wider at the surface of the cardbody (CB)—to accommodate the profile of the antenna module (AM). Thebooster antenna (BA) 130 may comprise turns (or traces) of wire (orother conductor) embedded in (or disposed on) the card body (CB), andmay comprise a number of components such as (i) a card antenna (CA)component 132 and (ii) a coupler coil (CC) component 134. It may benoted that, as a result of the recess (R) being stepped, a portion ofthe card body (CB) may extend under a portion of the antenna module(AM), more particularly under the module antenna MA.

FIG. 1A shows the ISO-7816 specification for a contact pad array (CPA).Eight contact pads C1-C8 are shown, The contact pads C1-C8 are locatedon the front surface of a smartcard. The dimensions are referenced tothe left and upper edges of the front surface of the card. For a 6-padlayout, the contact pads C4 and C8 may be omitted. The signalassignments for the contact pads are,

C1 VDD C2 RST_N C3 CLK C4 not used C5 VSS C6 not used C7 IO 1 C8 notused

The arrow in FIG. 1A (“insertion direction”) indicates the directionthat a smart card would be inserted into a reader, with contact pads C1,C2, C3 and C4 entering the reader first, followed by contact pads C5,C6, C7 and C8. (A 6 pad module does not have contact pads C4 and C8.)The “insertion direction” (or “card insertion direction”), as usedherein, may be defined as a direction parallel to a line drawn from C1to C5, or from C2 to C6, or from C3 to C7 or from C4 to C8.

FIG. 1B is a diagram of an exemplary contact pad array (CPA) comprisingan 8-pad pattern for ISO 7816 contact pads (CP), and illustrates that an8-pad layout may measure approximately 11.4 mm×12.6 mm. With a 2 mmspace around the contact pad array (CPA), the overall size (or the sizeof a recess R in a card body CB for receiving an antenna module AM) maybe 11.8 mm×13.0 mm.

FIG. 1C is a diagram of an exemplary contact pad array (CPA) comprisingan exemplary 6-pad pattern for ISO 7816 contact pads (CP), andillustrates that a 6-pad layout may measure approximately 8.0 mm×10.6mm. With a 2 mm space around the contact pad array (CPA), the overallsize (or the size of a recess R in a card body CB for receiving anantenna module AM) may be approximately 8.4 mm×11.0 mm.

FIG. 1D is a diagram showing conventional dimensions of a smart card(SC) having an ID-1 format, according to ISO/IEC 7810. The card body(CB) measures 53.98 mm×85.60 mm. A transponder chip module (TCM) isshown for insertion in the card body (CB). This figure illustrates theusual “form factor” for chip modules (in this case, a transponder chipmodule TCM), and their location in the smart card (SC).

FIG. 2A shows an antenna module (AM) comprising contact pads (CP)disposed on one side (or surface; top, as viewed) of a module tape (MT,or substrate) and a planar antenna (PA, or module antenna MA) and anRFID chip (CM, IC) disposed on the opposite side (or surface; bottom, asviewed) of the module tape (MT). The planar antenna (PA) is disposedaround the RFID chip (CM, IC). The planar antenna (PA) has two ends—aninner end disposed interior to the planar antenna (PA) (towards the RFIDchip), and an outer end disposed exterior to the planar antenna (PA).The inner end of the planar antenna (PA) may be connected directly(dashed line “---”) to a terminal (such as “LA”) of the RFID chip (IC,CM). However, the other, outer end of the planar antenna (PA) must“cross over” the planar antenna (PA) in order to be connected (dashedline “---”) with a second terminal (such as “LB”) of the RFID chip (IC,CM). This can be done with interconnect traces (not shown) on theface-down (bottom, as viewed) side of the module tape (MT).Alternatively, as indicated in FIG. 2B, the outer end of the planarantenna (PA) structure may connected, through the module tape (MT) to anouter end of a connection bridge (CBR) disposed on the face up (top, asviewed) side of the module tape (MT), the connection bridge (CBR) canextend to a position corresponding to (above) the interior of the planarantenna (PA) structure, and a connection can be made from the inner endof the connection bridge (CBR), through the module tape (MT) to a secondterminal (such as “LB”) of the RFID chip (IC, CM).

FIG. 2B shows an antenna module (AM) or transponder chip module (TCM)200 having a contact pad array (CPA) 202 comprising of 8 contact pads(C1-C8). The transponder chip module (TCM) also has two connectionbridges (CBR-1, CBR-2) 210, 212 on its contact (face-up) side of themodule tape (MT, not shown). An RFID chip (CM, IC, not shown) and amodule antenna (MA, shown in dashed lines) may be disposed on theface-down side (not visible) of the module tape (MT). A border is shownaround the transponder chip module (TCM), which may represent an opening(WO) in a card body (CB, or inlay substrate) for the transponder chipmodule (TCM).

The connection bridges (CBR-1, CBR-2) and contact pads (C1-C8) may beformed from a common conductive layer or foil of copper (for example),such as on a single-sided module tape (MT) which may have a conductivelayer (or foil) on its face-up side having a thickness of 35 μm. Themodule tape (MT) may also be double-sided, having conductive layers(foils) on both its face-up and face-down sides. Having two connectionbridges (CBR-1, CBR-2) may be useful in circumstances (i) when there aretwo module antennas (MA-1, MA-2), or (ii) when there is a single moduleantenna (MA) with a center-tap, or (iii) when there is a single moduleantenna (MA) with both of its ends oriented outward (and otherwiseneeding to cross-over the antenna structure AS).

The input capacitance of an RFID chip can vary with different productionbatches of silicon. To compensate for drifts in the input capacitance,the length of the last turn of the module antenna can be varied byhaving electrical taps at different positions along its length. Byselecting the appropriate length, the loaded resonance frequency of theantenna can be tuned to optimize performance. Alternatively, capacitivestubs can be laser trimmed to accomplish the same objective. Thesetechniques allow for trimming the performance of the module antenna (MA)for different chip batches

The module antenna (MA) may be a planar antenna (PA) which may be anetched (chemical or laser) antenna structure (AS). Alternatively, themodule antenna (MA) may be a non-planar, wire-wound antenna structure(AS).

The connection bridge (CBR-1) 210 is shown disposed adjacent to andabove (as viewed) the C1 contact pad, is generally “L-shaped”, andextends from an outer position (indicated by a round dot “•”) whichcorresponds to a position which is without (external to) the moduleantenna (MA) on the other side of the module tape (M) to an innerposition (indicated by an “X”) which corresponds to a position which iswithin (internal to) the module antenna (MA) on the other side of themodule tape (MT). Connections of components on the underside (face downside) of the module tape (MT) may be made to the connection bridge(CBR-1) to achieve interconnects (such as illustrated in FIG. 2A) whichmay otherwise require troublesome cross-overs or additional interconnectlayers. Notably, in this illustration, an outer end of the moduleantenna (MA) on the underside of the module tape (MT) may be connectedto the outer position (“•”) of the connection bridge CBR-1, and aterminal of the RFID chip (not shown, see FIG. 2A) may be connected tothe inner position (“X”) of the connection bridge CBR-1.

The second connection bridge (CBR-2) 212 is shown disposed adjacent toand above the C5 contact pad, and may be substantially a mirror image ofthe connection bridge (CBR-1), may be used to effect other or additionalconnections (not shown or described), and will not be described further.Having two connection bridges is optional. In cases where only oneconnection bridge is needed, the connection bridge (CBR-2) may suffice.Connection bridges may alternatively or additionally be positioned belowthe contact pads (CP) of the contact pad array (CPA), rather than aboveit. For example, in a 6-pad module which does not have the C4 or C8contact pads, what may otherwise appear to be the C4 or C8 contact padsmay in fact be connection bridges (CBR-3, CBR-4).

Some additional characteristics of the L-shaped connection bridge (CBR-1or CBR-2) may include at least one of the following (described mainlywith respect to CBR-1, but applicable to CBR-2 as may be evident fromthe context):

-   -   The L-shaped connection bridge may have a first portion which is        external to the module antenna (MA) on the other side of the        module tape (MT), and may extend horizontally (as viewed) above        the C1 pad and parallel to the insertion direction, measuring        approximately 4 mm (in the insertion direction)×2 mm        (perpendicular to the insertion direction), and is “elongated”        (longer than it is wide).    -   The L-shaped connection bridge may have a second portion, which        is generally perpendicular to the insertion direction, such as        extending vertically (as viewed) next to the C1 pad, and        extending from an end of the first portion to a position which        is within the contact pad array, between the C1 and C5 pads, and        may measure approximately 2 mm (in the insertion direction)×4 mm        (perpendicular to the insertion direction), and is “elongated”        (longer than it is wide).        -   In FIG. 2B, there is a vertical dashed line in the            connection bridge (CBR-1) 210. To the left of the line is            the first portion 210 a (parallel to the insertion            direction) of the connection bridge, to the right of the            line is the second portion 210 b (perpendicular to the            insertion direction) of the connection bridge.            Laser-Etched Antenna Structures (LES)

U.S. Ser. No. 14/281,876 filed 19 May 2014 (US 20140284386 25 Sep. 2014)discloses LASER ABLATING STRUCTURES FOR ANTENNA MODULES FOR DUALINTERFACE SMARTCARDS. Laser etching antenna structures for RFID antennamodules (AM) and combining laser etching and chemical etching aredisclosed. Limiting the thickness of the contact pads (CP) to less thanthe skin depth (18 μm) of the conductive material (copper) used for thecontact pads (CP). Multiple antenna structures (AS1, AS2) in an antennamodule (AM), and incorporating LEDs into the antenna module (AM) orsmartcard (SC) are also disclosed.

Generally, the transponder chip modules (TCM) disclosed herein may havea copper layer for forming a planar module antenna (MA, PA) which mayhave a thickness greater than or almost equal to the skin depth ofcopper (˜18 μm), for example 18 μm-35 μm, but it could also be 12 μm.The module antenna (MA) may be directly underneath the contact pads (CP)or connection bridges (CBR).

Generally, in practice, the thickness of metal cladding (metal layer ML,conductive layer CL) on one or both sides of a single-sided ordouble-sided module tape (MT), respectively, which may be laser-etchedto form contact pads (CP) on the face-up side of the module tape (MT), aplanar antenna (PA) on the face-down side of the module tape (MT), and acoupling frame (CP) on either side of the module tape (MT) is not lessthan 18 μm. A coupling frame (CF), described hereinbelow, should have athickness greater than the electromagnetic transparency of the metallayer in question. In the case of single- or double-sided copper-cladmodule tape (MT), the metal layer typically has a thickness of 18 μm or35 μm.

Laser etching is a form a laser ablation where material may be removedfrom a typically planar sheet (or foil) of material, and has someadvantages over conventional wet etching (chemical etching). A laseretch can proceed more uniformly through the material being etched, andcan also be controlled such as by increasing or decreasing the laserpower and subsequent etching at various portions of a pattern beingetched, in a highly-controllable manner. (With conventional wet/chemicaletching, the width of the etch may be tapered, narrowing from thesurface of the material being etched to the bottom of the etchedfeature. In contrast therewith, with laser etching, straight walletching can be achieved whereby the sides of the feature being etchedmay be substantially parallel with one another.)

Using laser etching, the spaces between tracks of an antenna structure(AS, MA, PA) may be dimensionally equal to the width of the laser beam,such as approximately 25 μm. The tracks themselves may have a width of25-100 μm. If a coupling frame (CF) is formed from the same metal layer(ML) as the planar antenna (PA), a gap (space) between the outer trackof the planar antenna (PA) and an inner edge (IE) of the coupling frame(CF) may also be equal to the width of the laser beam, such asapproximately 25 μm. After plating, the dimension of the spaces/gap maybe smaller, by a few microns, such as 20 μm.

The antenna (or antenna structure AS) may be laser etched from a copperlayer (cladding or foil), which may have a thickness less than the skindepth of copper (18 μm), forming a number of tracks separated by adistance approximately equal to the width of the laser beam, such asapproximately 25 μm. Subsequent to laser etching, the antenna structuremay be plated, which may reduce the distance between tracks toapproximately 20 μm (for example). This may result in increasedperformance of the antenna structure, and the overall antenna module AM(or transponder chip module (TCM)), and reduce performance constraintson the performance of a booster antenna (BA) in the card body (CB) ofthe smartcard (SC). The track width may be less than 100 μm, and thespacing between tracks may be less than 50 μm.

The antenna structure (AS) may be formed by laser etching, having anumber of (such as 10 or 12) tracks which are disposed substantiallyplanar with one another on a module tape (MT) or other suitablesubstrate, in a generally rectangular spiral pattern. The spacingbetween tracks may be on the order of 25 μm, or less (such as 20 μm,after plating).

As described in U.S. Ser. No. 14/465,815 filed 21 Aug. 2014, the trackwidth on the laser-etched antenna structure (LES) can be varied, fromend-to-end, to improve performance, in contrast with an antennastructure having a single (constant) track width. By way of analogy,this could be viewed as more than one antenna, each having a differenttrack width, connected in series with one another. As an example, afirst portion of an antenna structure may have a track width of 100 μm,another portion may have a track width of 50 μm. Additional portions mayhave other track widths. The spacing between tracks may also be varied.For example, the spacing between some tracks may be 25 μm or less, thespacing between some other tracks may be more than 25 μm. The ability tovary track width and spacing may be helpful in fine-tuning theperformance of the module, with attendant benefits in activationdistance (for example).

Coupling Frames

As mentioned in U.S. Ser. No. 14/465,815 filed 21 Aug. 2014, a smartcard(SC) may comprise an electrically-conductive layer, referred to hereinas a “coupling frame” (CF) disposed in the card body (CB) around atleast two sides (or 180°) of a transponder chip module (TCM) so as to bein close proximity with the module antenna (MA) in the transponder chipmodule (TCM). The coupling frame (CF) may nearly completely surround thetransponder chip module (TCM), such as all four sides (or 360°) thereof,minus a slit (S). The slit (S) may be very small, such as 50 μm. Acoupling frame (CF), at least partially surrounding a transponder chipmodule (TCM) and residing substantially on the same plane as thelaser-etched antenna structure (LES) in a card body, document or tag,without creating a closed circuit around the transponder chip module(TCM) by leaving at least one space or gap as an open circuit such as acut-out, slit or slot in the coupling frame (CF), may increase theamplitude of the resonance curve of the transponder chip module (TCM)with minimal frequency shift when interrogated by a reader, and mayincrease the activation distance.

As further described in U.S. Ser. No. 14/465,815, a coupling frame (CF),should be thick enough to conduct electricity and absorb anelectromagnetic wave at a frequency of interest and enhance couplingbetween the transponder chip module (TCM) and an external reader (suchas in FIG. 1). The coupling frame (CF) may be closely adjacent to, butnot completely encircle (substantially surround), the transponder chipmodule (TCM), and may extend from adjacent the transponder chip module(TCM) to one or more outer edges of the metal layer (ML), which may besubstantially coincident with the outer edges of the card body (CB).

As further described in U.S. Ser. No. 14/465,815, a metal surface or aconductive surface of suitable thickness and dimension acting as acoupling frame (CF) can replace (or obviate the need for) a boosterantenna (BA) in a dual interface smartcard (SC). The coupling frame in acard body (CB), tag, document or the like, may act as a capacitivecoupling antenna, concentrating the electromagnetic field around thetransponder chip module (TCM) which may have a laser-etched antennastructure (LES).

It should be understood that the concepts associated with the couplingframe (and slotted metal layer in a card body), disclosed herein mayprovide performance benefits with other than laser-etched antennastructures (LES), such as with chemically-etched antenna structures(CES).

Generally, both laser-etched antenna structures (LES) andchemically-etched antenna structures (CES) may be considered to be andreferred to herein as planar antenna (PA) structures. A planar antenna(PA) structure may be may be connected with an RFID chip (IC, CM) toform a transponder chip module (TCM) or antenna module (AM), and mayalso be referred to as a module antenna (MA). The planar antenna (PA)may be referred to as a module antenna (MA) or as an antenna structure(AS).

The performance of a planar antenna (PA) structure in a transponder chipmodule (TCM) may be enhanced by surrounding the antenna structure (AS)with a metal frame (MF), or coupling frame (CF), in the card body (CB)of the smart card (SC).

The coupling frame, may be smaller than ID-1 format, such as half orquarter ID1 size. The ID-1 format (ISO/IEC 7810) specifies a size forcards of 85.60 mm×53.98 mm (3.370×2.125 in) and rounded corners with aradius of 2.88-3.48 mm. It is commonly used for banking cards (ATMcards, credit cards, debit cards, etc.). It is also used for drivinglicenses in many countries. This format is also used for personalidentity cards in some countries, automated fare collection system cardsfor public transport, in retail loyalty cards, and it is a fairly commonformat for business cards. The United States Passport Card, as well asmost EU identity cards also use the ID-1 format.

The ISO/IEC 7810 standard defines four card sizes: ID-1, ID-2, ID-3 andID-000. [3]

Format Dimensions Usage ID-1 85.60 × 53.98 mm   Most banking cards andID cards ID-2 105 × 74 mm German ID cards issued prior to November 2010ID-3 125 × 88 mm Passports and visas ID-000  25 × 15 mm SIM cards

All card sizes have a specified thickness of 0.76 mm (0.030 in).

The present invention is not limited to any particular card size format.It is directed to a capacitive coupling enhanced (CCE) transponder chipmodule (TCM) which can function on its own, and which may be implantedin a smart card (SC) without requiring a booster antenna (BA).

Capacitive Coupling Enhanced (CCE) Transponder Chip Module (TCM)

Generally, a coupling frame (CF) may be incorporated into an antennamodule (AM) or transponder chip module (TCM), and may be formed from thesame conductive layer (CL) as the contact pads (CP) on the face-up sideof the module tape (MT). Alternatively, the coupling frame (CF) (oradditionally, a second coupling frame) may be formed from the sameconductive layer (CL) as a module antenna (MA), such as an etched planarantenna (PA), on the face-down side of the module tape (MT). Such atransponder chip module (TCM) with a coupling frame (CF) integratedtherewith may be referred to herein as a “capacitive coupling enhanced”(CCE) transponder chip module (TCM).

The coupling frame (CF) may be in the form of a ring (such as arectangular ring) having an opening (OP), an inner edge (IE) whichdefines the opening, and an outer edge (OE). A discontinuity which maybe a slit (S) or a non-conductive stripe (NCS) may extend from the inneredge (IE) or opening (OP) to the outer edge (OE) so that the ring of thecoupling frame (CF) is an open loop (discontinuous) conductor having twoends and a gap (which is the slit) therebetween.

The coupling frame (CF) may be disposed with its inner edge (IE) closelyadjacent to and partially surrounding the module antenna (MA) of atransponder chip module (TCM), and may be substantially coplanar withthe module antenna (MA). The coupling frame (CF) may surround at leasttwo sides of the planar antenna (PA) structure, such as three sidesthereof, or all four sides (except for the slit). When the term“partially surrounding” is used herein, it generally may refer to such acoupling frame (CF) which substantially surrounds (except for the slit,slot or gap) the module antenna (MA) of the transponder chip module(TCM). The coupling frame (CF) comprises a suitableelectrically-conductive material capable of interacting with RF from themodule antenna (MA) and an external RFID reader, enhancing couplingbetween the transponder chip module (TCM) and the external reader.

Both of the inner edge (IE) and the outer edge (OE) of the couplingframe (CF) may have the same geometric form (shape), such asrectangular. The inner edge may have a geometric form (such assubstantially rectangular) corresponding to the geometric form of themodule antenna (MA). The outer edge (OE) of the coupling frame (CF) mayhave a different geometric form (such as round or elliptical).

According to some embodiments of the invention, at least one couplingframe (CF) may be formed or disposed on a common substrate, such as anepoxy—glass module tape (MT) or chip carrier tape (CCT) with at leastone of:

-   -   an RFID chip (IC, or CM), and    -   an antenna structure (AS) which may be a module antenna (MA) or        a planar antenna (PA),        -   a planar antenna (PA) structure may be a laser-etched            structure (LES) or a chemically etched structure (CES),

A transponder chip module (AM, TCM), which may be incorporated into asmartcard (SC), may comprise an array of typically 6 or 8 contact pads(CPs) for interfacing with an external contact reader (e.g., ISO 7816).One or more connection bridges (CBRs) in the transponder chip module(TCM) may be used for making interconnections between components (suchas the module antenna MA and RFID chip IC) within the transponder chipmodule (TCM). The contact pads (CPs) and connection bridges (CBRs) maybe formed from a common conductive layer on the front (face-up) surfaceof the transponder chip module (TCM). Other isolated features may beformed from the conductive layer, such as decorative strips or areaswhere logos may be presented. The transponder chip module (TCM) may haveboth contact (ISO 7816) and contactless (ISO 14443, 15693) interfaces.See, for example, US 20140104133, particularly FIGS. 1, 1A, 21 and 21A-Ethereof.

Some of the concepts disclosed with respect to coupling frames (CF) onthe module tape (MT) of a capacitive coupling enhanced (CCE) transponderchip module (TCM) may be applied to coupling frames (CF) incorporatedinto the card body (CB) of a smart card (SC), and vice-versa. Couplingframes CF) in card bodies (CB) may be disclosed in the aforementionedcommonly-owned, copending U.S. Ser. No. 14/465,815 filed 21 Aug. 2014.Regarding such coupling frames which are in card bodies (such as in“metal cards”), some may comprise titanium, some others may comprisestainless steel, tungsten or aluminum, and some others may comprise adielectric layer with a deposited layer of metal.

Generally, in some embodiments of a coupling frame (CF) disclosed in acard body (CB), a planar layer or sheet or foil or cladding of aconductive material may be integrated into the card body (CB) and extendsubstantially to the periphery of the card body (CB). An ISO card bodymay have a dimension of 85.60 mm×53.98 mm/s63

An opening (MO, OP) may be formed in the coupling frame (CF), which maybe approximately the size of an antenna module (AM) or transponder chipmodule (TCM) (either of which may simply be referred to as “module”)which may be,

-   -   for a 6 pad module 8.0 mm×10.6 mm    -   for an 8 pad module, 11.4 mm×12.6 mm

The metal of the coupling frame (CF) serves at least two purposes. Itmay add weight to the smart card (SC), for vanity purposes (a betterfeel, and sound when tapping on a table). It also may enhance theelectrical functionality (such as read/write distance) of the smartcard. A typical metal for the coupling frame (CF) may be titanium.

Plating or Depositing Metal on a Dielectric

To achieve the purpose of adding weight to a smart card, some dielectricmaterials may be used. However, these dielectric materials are notelectrically conductive.

To achieve the purpose of enhancing the electrical functionality of thesmart card, the conductive coupling frame (CF) may be formed (created,fabricated) on a dielectric substrate, using any suitable means ofdepositing (sputtering, or growing, or including electroless plating).Alternatively, a conductive layer, such as a metal foil, may beadhesively attached to the dielectric substrate. In either case, ablanket layer of conductive material may be patterned as a couplingframe (CF) either before, during or after being disposed on thedielectric substrate.

Another method to incorporate a coupling frame (CF) into (for example) asmart card (SC) made from a dielectric material is to form the smartcard (SC) from more than one layer of material. One or more of thelayers may be processed to have a recess (or cavity) in a surfacethereof for receiving the coupling frame (CF), so that the couplingframe (CF) may be substantially flush with the surface. The couplingframe (CF) may be disposed in a cavity in the card body (CB). The cavityfor the coupling frame (CF) may be sized and shaped to accommodate othercomponents including a screen printed, gravure printed, chemicallyetched or wire-embedded booster antenna (BA) on a suitable substrate. Tocomplete the card construction the card layers may be laminated togetherusing some form of adhesive or binding agent. The use of a couplingframe (CF) may have advantages over traditional booster antenna (BA)systems in that the coupling frame (CF) can be formed from a foil ofsolid metal with extremely high thermal resistance. This permits theplacement of the coupling frame (CF) inside the card at an early stageof manufacture of the cards.

Another way to incorporate a coupling frame (CF) into a card body (CBmay be to start with a coupling frame (CF), and grow or extrude amaterial such as ABS (Acrylonitrile butadiene styrene) around thecoupling frame (CF).

A multi-layer card body (CB) may require subsequent high temperatureprocessing (laminating) to fuse the layers of the card. Since a couplingframe (CF) made from metal foil (for example) may be highly thermallyresilient, the laminating process should have no negative effect on thecoupling frame (CF).

The concept of a metallized coupling frame (CF) can be applied to cardsmade from a unibody construction of electrically insulating material(e.g. a, polymer composite). The concept can be extended to cards madefrom composite materials containing metallic particles or other fillersresiding inside an insulating matrix.

A coupling frame (CF) may be formed on such unibody card bodies byelectroless deposition of a metal (e.g. copper, aluminum, nickel)followed by subsequent growth of additional metal by electroplating. Themetallization can be applied to one or both sides of the card body (CB).The coupling frame (CF) may be then be left as exposed metal, or it maybe covered by a conformal dielectric coating or other insulating film to(i) prevent ESD (electrostatic discharge), (ii) obscure the presence ofthe coupling frame (CF), and (iii) protect the metallization from wearand tear during use of the card. Alternatively a metal foil, or laminatecontaining a metal foil, may be affixed to one or both surfaces of thecard. The metal foil may be patterned in a way to serve as a couplingframe (CF).

Transponder Chip Module (TCM) with a Coupling Frame (CF)

FIG. 3A shows the face-up side of a capacitive coupling enhanced (CCE)transponder chip module (TCM) 300, which may comprise:

-   -   a module tape (MT) 301 or chip carrier tape (CCT),    -   a transponder chip module (TCM) 302 having        -   a module antenna (MA) 304 which may be a planar antenna            (PA), and an RFID chip (IC) 305 on the face-down side of the            module tape (MT), shown in dashed lines, and        -   contact pads (CP) C1-C8) and connection bridges (CBR-1,            CBR-2) on the face-up side of the module tape (MT),    -   a coupling frame (CF) 320 disposed on either side of the module        tape (MT), surrounding and closely adjacent to the module        antenna (MA), so that it may interact with the module antenna        (MA) and enhance coupling between the transponder chip module        (TCM) and an external contactless reader.

The transponder chip module (TCM) itself corresponds generally to thetransponder chip module (TCM) shown in FIG. 2B, but a coupling frame(CF) has been added.

In many embodiments of antenna modules (AM) and transponder chip modules(TCM), the RFID chip (IC) is disposed at an area of the module tape (MT)prepared for mounting the RFID chip (IC), and may be installed on themodule tape (MT) and connected with the module antenna (MA) at a laterdate and at a different location than where the module tape (MT) withits contact pads (CP) and planar module antenna (PA, MA) is initiallymanufactured. This would apply to the capacitive coupling enhancedtransponder chip modules (CCE-TCM) disclosed herein. The module tape(MT) with its contact pads (CP) and planar module antenna (PA, MA) maythus be considered to be an “interim product”. In FIG. 3A, the dashedline 305 is representative of this area for mounting the RFID chip (IC).In other figures, wherever an RFID chip (IC) is shown or described, thisis also indicative of an area for mounting the RFID chip (IC).

The module tape (MT, CCT) may comprise epoxy-glass, 35 mm wide. Somedimensions for the transponder chip module (TCM) and coupling frame (CF)are shown. FIGS. 5A, 5B show the module tape (MT) better. The moduletape (MT) serves as a substrate upon which the transponder chip module(TCM) is constructed. The module tape (MT) may be referred to as a “chipcarrier tape” (CCT).

A planar antenna (PA) 304 may be provided on an opposite (face-down)side of the module tape (MT) of the Transponder Chip Module (TCM), andis shown only generally in dashed lines. This corresponds generally tothe transponder chip module (TCM) shown in FIG. 2B. The planar antenna(PA) may be laser-etched. Alternatively, the planar antenna (PA) may bechemically etched. Only a few turns (or tracks) of the planar antenna(PA) are shown, for illustrative clarity. There may be 10-12 turns,depending on the input capacitance of the RFID chip. The outer turn ofthe planar antenna (PA) may extend nearly to a position corresponding tothe periphery of the contact pad array on the other side of the moduletape (MT).

A coupling frame (CF) 320 may be disposed on a face-up side of themodule tape (MT), and is shown surrounding the contact pads (CP) andconnection bridges (CBR) 310, 312. In this example, the coupling frame(CF) is disposed on the same face-up side of the module tape (MT) as thecontact pads (CP) and connection bridges (CBR), and may be formed fromthe same conductive layer (CL) or metal layer (ML) that forms thecontact pads (CP) and connection bridges (CBR). The conductive metallayer (CL, ML) may be, for example, 18 μm or 35 μm thick copper. Thecoupling frame (CF) may extends around the contact pad array (CPA),including around the connection bridges (CBR). If the coupling frame(CF) is disposed on the face-down side of the module tape (MT), it maybe formed from the same conductive layer (CL) or metal layer (ML) thatforms the etched planar module antenna (MA, PA).

The coupling frame (CF) has an inner edge (IE) 322 defining an opening(OP) 323 in the coupling frame (CF) and has an outer edge (OE, orperiphery) 324. A slit (S, or slot, or gap) (S) 326 extends from theinner edge (IE) or opening (OP) of the coupling frame (CF) to the outeredge (OE) thereof, so that the coupling frame (CF) forms an open-loopconductive element (“C” shaped) having two ends (end-1, end-2) separatedby the slit (S). The slit (S) may measure approximately 50 μm (betweenthe opposing ends of the coupling frame), or smaller, such as 25 μm or10 μm. The slit (S) results in the two opposing ends of the couplingframe being closely spaced with one another, so that the coupling framemay nearly completely encircle the transponder chip module (TCM) 302A,and its module antenna (MA).

On the other (face-down) side of the module tape (MT), the planarantenna (PA) and connection traces (not shown) to the bond pads (BP),may be formed from a metal layer (e.g., 18 μm or 35 μm thick copper)with a thickness similar to the metal layer (ML) that forms the contactpads (CP) and connection bridges (CBR).

The coupling frame (CF) may be disposed on the face-down side of themodule tape (MT), surrounding the module antenna (MA), closely spacedtherefrom, and coplanar therewith. When the coupling frame (CF) isdisposed on the face-up side of the module tape (MT), surrounding thecontact pads (CP), it is offset from the module antenna (MA) only by thethickness of the module tape (MT), and may be considered to besubstantially coplanar with the module antenna (MA). And, being on theopposite side of the module tape (MT) from the module antenna (MA), aninner portion of the coupling frame (CF) can overlap at least some outerturns of the module antenna (MA). The module tape (MT) may have athickness of approximately 75 μm-100 μm. (The thickness of the glassepoxy layer may be in the range from 70 to 100 μm, before the copperlayer(s) are added.)

The outer periphery of the contact pad array (CPA) is shown as beingrectangular. An inner edge of the coupling frame (CF) is shown as beingrectangular. A gap 328 separates the inner edge of the coupling frame(CF) from the outer periphery of the contact pad array (CPA) andconnection bridges (CBR-1, CBR-2). The gap may be approximately 100 μm,or less. An outer edge of the coupling frame (CF) may also berectangular. Some exemplary dimensions (approximate) may be:

-   -   contact pad array (CPA), 10.6 mm×8.0 mm (for a 6 pad array)        -   area of contact pad array (CPA), approximately 85 mm²    -   area of the planar antenna (PA) structure, somewhat less than        that of the CPA    -   inner edge of coupling frame, 10.7 mm×8.1 mm        -   opening in the coupling frame (CF) for the contact pad array            (CPA), 87 mm²    -   outer edge of coupling frame, 26 mm×28 mm (728 mm²)        -   area of coupling frame (CF), 728 mm²-87 mm²=641 mm²

When the coupling frame (CF) is disposed on the same face-down side ofthe module tape (MT) as the planar antenna (PA), a gap between the inneredge of the coupling frame and an outer turn (or track) of the planarantenna (PA) may similarly be approximately 100 μm, or less.

In this example, the coupling frame (CF) has an area which isapproximately 7 times larger than the area of the planar antenna (PA)structure. For an 8 pad array, this ratio may be less.

-   -   all dimensions approximate (exemplary)    -   the coupling frame (CF) may be disposed on either side of chip        carrier tape (CCT)—i.e., on the “face-up” contact side or on the        “face-down” chip (or bond) side.    -   the coupling frame (CF) may be much larger than shown    -   a second coupling frame (CF-2, not shown) may be disposed on the        tape, and may be connected with the illustrated coupling frame        (CF-1)

The slit (S) in FIG. 3A is shown extending from the opening (OP), whichis defined by the inside edge of the coupling frame (CF), to the outsideedge thereof, at a position to the left of the transponder chip module(TCM) 304. The slit (S) makes the coupling frame (CF) an open loop—“C”shaped, having two ends. It should be understood that the slit (S) maybe located elsewhere, such above the transponder chip module (TCM), tothe right of the transponder chip module (TCM), or below the transponderchip module (TCM). It is important that the slit (S) extends anywherefrom the inner edge of the coupling frame (CF) to the outer edgethereof, thereby making the coupling frame (CF) a conductive open loop,having two ends. In other words, the coupling frame is a “C”, not an“O”.

FIG. 3A-1 shows a detail of the two ends of the coupling frame (CF)shown in FIG. 3A. Here, the ends (end-1, end-2) are square and parallelwith one another, the coupling frame (CF) having been intersected at aright angle by a straight slit (S). The slit (S) results in two opposingends of the coupling frame being closely spaced with one another, sothat the coupling frame may nearly completely encircle the transponderchip module (TCM) 302A (or 302B, below). The coupling frame (CF) extendsnearly entirely around the transponder chip module (TCM)—such as “359°”around it (360° minus the slit S).

FIG. 3A-2 shows a variation of the two ends of the coupling frame (CF)shown in FIG. 3A. Here, the ends (end-1, end-2) are each stepped, thecoupling frame (CF) having been intersected by a non-straight slit (S).In this example, the slit (S) is stepped. The coupling frame (CF)extends nearly entirely around the transponder chip module (TCM)—such as“359°” around it (360° minus the slit S). A similar result may accruewith the slit (S) is other than perpendicular to the outer edge (OE) ofthe coupling frame (CF), for example, extending through the couplingframe (CF) from the outer edge to the inner edge thereof, at a 45°angle. Compare FIG. 3D. The dashed line passing through the ends of thecoupling frame indicates that any line perpendicular to an outer edge ofthe transponder chip module (TCM), or perpendicular to the inner edge(IE) of the coupling frame (CF), will always intersect at least aportion of the coupling frame (CF)—in which case the coupling frame (CF)may be said to completely surround the transponder chip module (TCM) andits module antenna (MA). Compare FIG. 3A wherein the dashed line passesthrough the slit (S).

An alternative to forming a slit (S) is to render a comparable area ofthe conductive metal layer (ML) of the coupling frame (CF)non-conductive, providing an electrical discontinuity (rather than aphysical slit) to ensure that the coupling frame is open-loop. Such anon-conductive discontinuity may be referred to as a “non-conductivestripe” (NCS).

FIG. 3B illustrates a capacitive coupling enhanced (CCE) transponderchip module (TCM) 300B comprising a transponder chip module (TCM) 302and a coupling frame (CF) 324 disposed on a module tape (MT) 301 such as(similar to the one) shown in FIG. 3A, and similar elements may besimilarly numbered (suffix “B” rather than “A”). The coupling frame (CF)extends around the contact pad array (CPA), including around connectionbridge 310, with a gap 328 therebetween, and has a slit (S) 326 makingit an open loop, having an outer edge (OE), and an inner edge (IE)defining an opening (OP). The slit (S) extending from the opening (OP)to the outer edge (OE) results in two opposing ends of the couplingframe (CF) being closely spaced with one another, so that the couplingframe may nearly completely encircle the transponder chip module (TCM)302. An etched planar antenna (PA) 304 and RFID chip (IC) 305 may bedisposed on an opposite side of the module tape (MT).

As described above, the coupling frame (CF) may be disposed on theface-up side of the module tape (MT), surrounding the contact pads (CP)and overlapping (or being above) the module antenna (MA) on theface-down side of the module tape (MT). The module antenna (MA) may be aplanar antenna (PA) which may be laser etched.

A connection bridge (CBR) may be an isolated metal structure on theface-up (contact) side of the module tape (MT) for effecting connectionsbetween components such as the module antenna (MA, PA) and RFID chip(CM, IC) on the other, face-down side of the module tape (MT), moreparticularly to avoid the necessity for interconnect structures orcross-overs on the face-down (chip) side of the module tape (MT). Anexample of a connection bridge (CBR) is shown in US 20130146670, whereinit may be referred to as a connecting structure or contact bridge.

The coupling frame (CF) 320 may be extended to the interior of thecontact pad array (CPA), on the top (as viewed) of the contact pad array(CPA) between the C1 and C5 contact pads, and may serve as a connectionbridge (CBR) 310B effecting a connection between a first position(indicated by the dot “•”) which corresponds to a position which iswithout (external to) the module antenna (MA, PA) on the other side ofthe module tape (MT) and a second position (indicated by the “X”) whichis within (interior to) the module antenna (MA, PA) on the other side ofthe module tape (MT). Or, in other words, a connection bridge (CBR) maybe enlarged to nearly encircle the transponder chip module (TCM) toserve “double duty” as a coupling frame (CF). The coupling frame (CF)may be considered to be integral with the connection bridge (CBR), andvice-versa (a connection bridge may be extended around the contact padarray to serve as a coupling frame). The resulting “hybrid” connectionbridge (CBR)/coupling frame (CF) may have a surface area much much (>>)greater than the surface area of a normal contact pad (CP).

The coupling frame (CF) may be somewhat effective if it extends aroundat least two (of the four) sides of the contact pad array (CPA) may bemore effective if it extends around at least three sides of the contactpad array (CPA), and may be most effective if it extends around nearlyall four sides of the contact pad array (CPA), as shown. In the examplesset forth above, the coupling frame (CF) is formed in the same layer asthe connection bridge(s) and contact pads (CP), on the same side of themodule tape (MT), and extends substantially all around the contact padarray (except for the slit S). A coupling frame (CF) may be disposed onan opposite side of the module tape (MT), surrounding and closelyadjacent to the module antenna (MA), and may be most effective if itextends completely around the module antenna (MA), except for the slit(S).

The coupling frame (CF) may be integral with (FIG. 3B) or connected inany suitable manner with the connection bridge, if desired. When theconnection bridge is connected with an end of a module antenna (MA), theconnection bridge (including, in some embodiments, the hybrid connectionbridge/coupling frame) may function as a capacitive extension of themodule antenna (MA). In a double-sided tape, a conductive layer on aside of the module tape opposite from the coupling frame may contributeto the capacitance of the coupling frame. The coupling frame/connectionbridge may be patterned with holes, slits and the like.

FIG. 3C shows that the coupling frame (CF) may be disposed on the sameside of the module tape (MT) or chip carrier tape (CCT) as the contactpads (CP), and indicates (by the cross-hatching) that it may be formedfrom the same conductive layer (CL) as the contact pads CP (andconnection bridges CBR). The slit (S) is not visible in thiscross-sectional view, which may be a cross-sectional view of thecapacitive coupling enhanced (CCE) transponder chip module (TCM) 300shown in FIG. 3A.

An RFID chip (CM, IC) may be disposed on the bottom (as viewed) side ofthe module tape (MT). In some subsequent views of other embodiments, theRFID chip may be omitted, for illustrative clarity. In some of thedescriptions presented herein, a capacitive coupling enhanced (CCE)transponder chip module (TCM) may be referred to simply as a transponderchip module (TCM), or in some cases as an antenna module (AM). And,typically, the module antenna (MA) may be a planar antenna (PA).

FIG. 3D shows that the coupling frame (CF) may be much wider than thetransponder chip module (TCM), such as nearly the entire width of a cardbody (CB) of a smart card (SC), such as approximately 80 mm wide. Thetransponder chip module (TCM) is disposed in the opening (OP) of thecoupling frame (CF). The module tape (MT) is shown in dashed lines. Thisfigure shows that the slit (S) may extend at an angle other thanperpendicular to the outer edge (OE). The dashed line (---) passingthrough the slit (S) illustrates that any line perpendicular to theouter edge (OE) of the coupling frame (CF) will always intersect thecoupling frame (CF)—in which case the coupling frame (CF) may be said tocompletely surround the transponder chip module (TCM) and its moduleantenna (MA). The module antenna (MA) and RFID chip (IC) are not visiblein this view. As mentioned previously, some concepts relating toincorporating a coupling frame (CF) on a module tape (MT) of acapacitive coupling enhanced (CCE) transponder chip module (TCM) may beapplied to incorporating a coupling frame (CF) into the card body (CB)of a smart card (SC), generally by substituting “module tape (MT)” for“card body (CB)”, and vice-versa.

FIGS. 3D-3I, 3N are views of the face-up side of the module tape (MT)and omit a showing of the module antenna (MA) on the other side of themodule tape (MT), for illustrative clarity. The module antenna (MA) isshown clearly in FIG. 3B (also a view of the face-up side), as well asin some cross-sectional views (for example, in FIGS. 3J,K,L).

FIG. 3E shows that the slit in the coupling frame (CF) may be other thanstraight, such as a zigzag slit or a slit which is becomes wider ornarrow along its length.

FIG. 3F shows that a coupling frame (CF) may have two slits (slit-1,slit-2), each extending from its inner edge to its outer edge, anddisposed (for example) on opposite sides of the transponder chip module(TCM). (This may be considered to be two C-shaped coupling frames, eachsurrounding only one side and portions of two adjacent sides of thetransponder chip module TCM, with their ends facing each other.) A logomay be printed on or etched into the coupling frame (CF) (see FIG. 3N).

FIGS. 3G and 3H illustrate transponder chip modules (TCM) havingcoupling frames (CF) integrated therewith, and show that the transponderchip module (TCM) may have other than a rectangular shape (profile). InFIG. 3G, the overall shape of the transponder chip module (TCM) iselliptical, and the slit (S) is oriented towards the left. In FIG. 3H,the overall shape of the transponder chip module (TCM) is round, and theslit (S) is oriented towards the right.

FIG. 3I illustrates that the coupling frame (CF) of a transponder chipmodule (TCM) may extend a asymmetrically from the contact pad array(CPA). For example, the coupling frame may extend approximately 10 mm tothe left of the contact pad array (CPA), and approximately 50 mm to theright of the contact pad array (CPA), corresponding to the left andright edges of a smart card (SC, shown in dashed lines), respectively.

FIG. 3J shows that the coupling frame (CF) may be disposed on a side ofthe module tape (MT) or chip carrier tape (CCT) opposite to that of thecontact pads (CP) and connection bridges (CBR)—in other words, on thesame (face-down) side as the planar antenna (PA) structure. In thiscase, the coupling frame (CF) may be substantially coplanar with theplanar antenna (PA) structure. An RFID chip (IC) may be disposed on thebottom (as viewed) side of the module tape (MT).

Generally, the RFID chip (CM, IC) is traditionally disposed on theface-down side of the module tape (MT), although it could alternativelybe disposed on the face-up side of the module tape (MT). In the exampleof FIG. 3J, with the coupling frame (CF) on the face-down side of themodule tape (MT), the RFID chip (CM, IC) may be disposed on the couplingframe (CF), including outside of (external) to the planar antenna (PA),rather than its “traditional” location centered under the contact pads(CP). Generally, what is important is the location of the coupling frame(CF), more particularly its opening (OP) and slit (S), with respect tothe module antenna (MA, PA), and the RFID chip (IC) can be anywhere—allof these components (CF, MA, IC) (and the contact pads CP in the case ofa dual-interface transponder chip module TCM) being disposed on themodule tape (MT).

FIG. 3K shows that when the coupling frame (CF) is disposed on the sameside of the module tape (MT) or chip carrier tape (CCT) as that of thecontact pads (CP) and connection bridges (CBR), on an opposite side ofthe module tape (MT) from the planar antenna (PA). The planar antenna(PA) may be made larger, extending for example beyond the periphery ofthe contact pad array (CPA), and the coupling frame (CF) may overlap(albeit on an opposite side of the module tape MT) at least an outerportion of the planar antenna (PA) structure. An RFID chip (IC) may bedisposed on the bottom (as viewed) side of the module tape (MT).

In this example, the coupling frame (CF) has an opening (OP) which maybe smaller than the outer portion (outer turns) of the module antenna(MA) including, if the module antenna (MA) were larger, the opening (OP)may be smaller than the entire module antenna (MA). Nevertheless, theopening (OP) of the coupling frame (CF) may be generally concentric withthe module antenna (MA), its inner edge (IC) may be considered to bewithin the definition of “closely adjacent” to the module antenna (MA),and the coupling frame CF) may considered to be within the definition of“partially surrounding” the module antenna (MA).

It may be noted that the coupling frame (CF) shown in FIG. 3K is on anopposite side of the chip carrier tape (CCT) from the planar antenna(PA) structure, and therefore is not 100% coplanar with the planarantenna (PA) structure. However, given the small thickness(approximately 100 μm) of the chip carrier tape (CCT), the couplingframe (CF) may nevertheless be considered to be “substantially coplanar”with the planar antenna (PA) structure. The plane of the coupling frame(CF) is substantially (if not perfectly) parallel with the plane of theplanar antenna (PA) structure (since the two sides of the chip carriertape (CCT) are substantially parallel with one another). It may be notedthat the coupling frame (CF) shown in FIG. 3K overlaps at least aportion of the planar antenna (PA) structure. An inner portion of thecoupling frame (CF) may overlap some outer turns (tracks) of the planarantenna (PA) structure. (The chip carrier tape (CCT) or module tape (MT)may typically have a thickness of 70 μm or 110 μm, with copper claddingon one or both sides having a thickness of typically 12 μm, 18 μm or 35μm.

It may be noted that the inner edge (IE) of the coupling frame (CF)shown in FIG. 3K defines a central opening (OP) in the coupling frame(CF), and the contact pads (CP) may be formed in that opening. Thecontact pads (CP) are isolated metal structures, with gaps therebetween.A given contact pad (e.g., C5, which is ground) may be connected to,contiguous with, the coupling frame (CF). The opening (OP) in thecoupling frame (CF) may be aligned with (over, atop) the module antenna(MA) on the other side of the module tape (MT), and an inner portion(near the opening OP) of the coupling frame (CF) may overlap an outerportion (the outer tracks/turns) of the module antenna (MA). Thecross-dimension (e.g., inner diameter) of the opening (OP) may besmaller than the cross-dimension (e.g., outer diameter) of the moduleantenna (MA). This is facilitated by the coupling frame (CF) and moduleantenna (MA) being on opposite sides of the module tape (MT).

In FIG. 3J, with the coupling frame (CF) and module antenna (MA) on thesame side of the module tape (MT), achieving an overlap may require anadditional layer, and may require a coupling frame which is formed froma separate metal foil which is disposed on the module tape.Nevertheless, “as is”, with the coupling frame (CF) formed from the samemetal layer (ML) as the module antenna (MA), or planar antenna (PA), avery small gap (such as 25 μm) may be maintained between the inner edge(IE) of the coupling frame (CF) and an outer track of the module antenna(MA).

U.S. Ser. No. 14/465,815 filed 21 Aug. 2014 discloses a coupling framein a card body of a smart card, and positioned so that its inner edge isas close as possible to the module antenna. However, due to mechanicalconsiderations (such as allowing for milling the card body to accept theantenna module), it is difficult to maintain a very small gap betweenthe coupling frame and the module antenna, when they are strictlycoplanar with one another. FIG. 2C therein shows that an inner portionof the coupling frame can overlap some outer tracks of the moduleantenna (LES 212), but to allow for milling, the underlying couplingframe may be spaced by approximately 100 μm from the module antenna.

Maintaining a very narrow gap between the inner edge (IE) of thecoupling frame (CF) and the module antenna (MA) may be easier to achievewhen the coupling frame (CF) is integral with the module tape (MT),particularly when it is formed from the same metal layer (ML) as themodule antenna or the contact pads.

FIG. 3L shows that one coupling frame (CF-1) may be disposed on one sideof the module tape (MT) or chip carrier tape (CCT), and another couplingframe (CF-2) may be disposed on another side of the module tape (MT) orchip carrier tape (CCT). An RFID chip (not shown, compare FIG. 2A) maybe disposed on the bottom (as viewed) side of the module tape (MT).

FIG. 3L bears some resemblance to FIG. 4A of U.S. Ser. No. 14/465,815filed 21 Aug. 2014, which discloses SMARTCARD WITH COUPLING FRAME ANDMETHOD OF INCREASING ACTIVATION DISTANCE OF A TRANSPONDER CHIP MODULE.FIG. 4A therein illustrates an embodiment of a smartcard 400A having amultiple coupling frame stack-up. Here, there are two coupling frames(CF-1, CF-2) 421, 422 in different layers of the card body (CB),separated by a layer 423 of non-conductive material (such as PVC). Thestack-up comprises a front face card layer 424, a first coupling frame(CF-1) 421, an internal card dielectric layer 423, a second couplingframe (CF-2) 422 and a rear face card layer 426. The first couplingframe (CF-1) surrounds the top, left and bottom edges of the transponderchip module (TCM) 410, and extends to the top, left and bottom edges ofthe card body (CB), and has a module opening (MO-1). The second couplingframe (CF-2) surrounds the top, right and bottom edges transponder chipmodule (TCM), and extends to the top, right and bottom edges of thecard, and has a module opening (MO-2). In aggregate, the first andsecond coupling frames (which may be referred to as “420”) cover nearlythe entire surface of the card body 402 (less the area of thetransponder chip module TCM). An activation distance of 40 mm wasachieved. A similar concept of having two “partial” coupling frames maybe applied to a capacitive coupling enhanced (CCE) transponder chipmodule (TCM) such as shown (for example) in FIG. 3L herein, with onecoupling frame (CF-1) surrounding the transponder chip module (TCM) fromthe left, the other coupling frame (CF-2) surrounding the transponderchip module (TCM) from the right, in aggregate the two coupling framessurrounding the transponder chip module (TCM)

An overall coupling frame may comprise two or more substantiallyconcentric, substantially coplanar open loops (each loop is an opencircuit), formed on the same side of a single substrate. As used herein,“concentric” may refer to the openings in each of the loops beingsubstantially aligned with one another, and substantially aligned withthe module antenna (MA).

An overall coupling frame may comprise two or more substantiallyconcentric, open loops (each loop is an open circuit) formed on oppositesides of a single substrate, or on two substrates which will be stackedone atop the other. As used herein, “concentric” may refer to theopenings in each of the loops being substantially aligned with oneanother, and substantially aligned with the module antenna (MA).

FIG. 3M shows a purely contactless embodiment of the invention whereinthere are two planar module antennas (PA, MA) or antenna structures(AS)—a first planar antenna structure (PA-1) on one side of the chipcarrier tape (CCT) and a second planar antenna structure (PA-1) on anopposite side of the chip carrier tape (CCT). A single coupling frame CFis shown, on the bottom (as viewed) side of the chip carrier tape (CCT),but there may be two coupling frames CF-1 and CF-2 as shown in FIG. 3L,on each of the two sides of the chip carrier tape (CCT). An RFID chip(not shown, compare FIG. 2A) may be disposed on the bottom (as viewed)side of the module tape (MT).

FIGS. 3J,K,L,M are illustrative of an interim product for a transponderchip module (TCM)—namely a module tape (MT), prepared with contact pads(CP), one or more planar antennas (PA), and one or more coupling frames(CF). subsequently, an RFID chip can be mounted to the module tape (MT),and connected with the contact pads (CP) and planar antenna(s) (PA). Theresulting transponder chip module (TCM) would be a capacitive couplingenhanced (CCE) transponder chip module (TCM) by virtue of it having acoupling frame (CF) integrated therewith.

FIG. 3N shows a capacitive coupling enhanced transponder chip module(CCE-TCM) comprising a transponder chip module (TCM) and a couplingframe (CF), wherein the coupling frame (CF) measures approximately 14mm×25 mm, disposed in a card body (CB) of a smart card (SC). The 8-padcontact pad array (CPA) may measure approximately 11.4 mm×12.6 mm. Witha 2 mm space around the contact pad array (CPA), the overall size may be11.8 mm×13.0 mm. A logo (“LOGO”) or design may be printed on or etchedinto the coupling frame (CF).

Some Exemplary Dimensions may be (vertical×horizontal):

-   -   for a 6-contact TCM: 8.2 mm×10.8 mm    -   for an 8-contact TCM: 11.8 mm×13.0 mm    -   for the coupling frame (CF): 14.0 mm×25.0 mm    -   for the card body (CB): 53.98 mm×85.60 mm

As mentioned previously, the coupling frame concept may be implementedin the card body (CB) of the smart card (SC), rather than on the moduletape (MT) of the transponder chip module (TCM). However, generally, thecoupling frame (CF) may be more closely spaced adjacent to the moduleantenna (MA) when it is on the same module tape (MT) as the moduleantenna (MA).

FIG. 3O shows the contact pad array (CPA) of a transponder chip module(TCM) comprising eight contact pads (C1-C8). Two connection bridges(CBR-1, CBR-2) are shown above contact pads C1 and C5 of the contact padarray (CPA), respectively. The dark lines between the contact pads andconnection bridges represent conductive traces (CT) which may be formedfrom the same conductive layer (CL), or metal layer (ML) from which thecontact pads (CP) may be formed, such as by laser etching. Theconductive traces (CT) may extend between contact pads (CP) of thecontact pad array (CPA). The conductive traces (CT) may also extendaround the exterior of the contact pads (CP) and connection bridges(CBR).

One or more of the conductive traces (CT) may be connected with thecentral area of the contact pad array (CPA) protect againstelectrostatic discharge (ESD). This is indicated by the oval labeled“connection to ground”. Often, the central area of the contact pad array(CPA) is contiguous with the C5 contact pad, which is ground (VSS),

For electrostatic discharge (ESD) protection, discussed in greaterdetail hereinbelow the coupling frame (CF) may be connected with (linkedto, contiguous with) the C5 contact pad which is ground (earth). ESD mayoccur from someone touching the contact pads (CP) of the transponderchip module (TCM) and causing the RFID chip to fail. By grounding thecoupling frame with the chip, the discharge can be avoided.

The C5 pad on the face-up side of the module tape (MT) may be connected,in any suitable manner (as indicated by the “x”) with a coupling frame(CF shown in dashed lines) which may be disposed on the opposite,face-down side of the module tape (MT).

Multiple Module Antennas

The publication RFID Handbook: Fundamentals and Applications inContactless Smart Cards and Identification, Second Edition, KlausFinkenzeller, © 2003, John Wiley & Sons, incorporated by referenceherein, discloses (see, e.g., page 45) that load modulation creates twosidebands at a distance of a subcarrier frequency fs around thetransmission frequency of the reader. The actual information is carriedin the sidebands of the two subcarrier sidebands, which are themselvescreated by the modulation of the subcarrier.

In the transponder chip modules (TCM) disclosed herein, the side bandsmay be plus and minus 848 kHz on each side of the carrier (13.56 MHz).The sub-carrier of the side bands is modulated with the data signal.

Two coils (antenna 1, antenna 2) may be used in the transponder chipmodules (TCM) (connected to a high input capacitance chip, such asapproximately 60 to 90 pF), with each coil having a different resonantfrequency, for example 13 MHz and 14 MHz. When the two coils (antenna 1,antenna 2) are connected in series, the resonant frequency will bearound 13.5 MHz. Moreover, the Gaussian curve may not be a bell shape,but may have two humps (like a camel). In this manner, both sidebandsmay be covered, and there may be no loss of data.

Some of the embodiments disclosed herein show two separate moduleantennas (MA), which may be planar antennas (PA), and which maygenerally be referred to as antenna structures (AS). Other embodimentsmay be suggestive of having two antenna structures, or may be adaptableto having two antenna structures. When there are two (or more) antennastructures, or segments, they may interconnected in various ways, andmay be referred to in aggregate as the module antenna (MA).

Two antenna structures (PA-1, PA-2, or AS-1, AS-2), such as shown inFIG. 3M, whether on the same side or on opposite sides of the moduletape (MT) may be considered to be one overall module antenna (MA). Thetwo antenna structures (AS-1, AS-2) may be connected in any suitablemanner with one another, such as in series with one another, or inparallel with one another, or in “reverse phase” with one another (seeUS 20130075477), and a capacitor may be connected with the moduleantenna (MA). The two antenna structures (AS-1, AS-2) may be coplanarand concentric with one another. A connection between two antennastructures may be considered to be a “tap”. If there is one antennastructure (AS), it may have a center tap, or a tap which is not at thecenter.

A coupling frame (CD) may also be incorporated into a transponder chipmodule (TCM) having two antenna structures (S). As shown in FIG. 3M, twoantenna structures (PA-1, PA-2) may be disposed on opposite sides of themodule tape (MT), which may be compatible with double-sided module tape(epoxy glass substrate having copper cladding on both sides thereof).

FIG. 3M shows two planar antennas (PA-1, PA-2) on a single module tape(MT) for a single transponder chip module (TCM). This is representativeof a number of possible ways to have two antenna structures (AS), ormodule antennas (MA) in a transponder chip module (TCM), or antennamodule (AM). A number of other examples of having two antenna structuresor module antennas are disclosed in commonly-owned, copending U.S. Ser.No. 14/281,876 filed 19 May 2014 (US 20140284386, 25 Sep. 2014), forexample (referencing drawings therein):

-   -   FIGS. 2A,B show an antenna module (AM) having three antenna        structures (A,B,C). One antenna structures (A) is the main        antenna structure, the other antenna structures (B,C) may be        considered to be capacitive stubs.    -   FIG. 2C shows two module antenna segments (MA1, MA2) which are        arranged concentric with one another.    -   FIG. 2D is a diagram showing one possible way how the two        antenna segments may be connected with one another.    -   FIGS. 2E, 2F illustrate that the antenna MA may be formed on an        antenna substrate AST which may be substantially the same size        as and separate from a module substrate (or tape) MT, and        subsequently joined together.    -   FIG. 2G shows an antenna module AM comprising two module tape        layers MT1 and MT2, each layer having an antenna coil MA1 and        MA2, respectively.    -   FIG. 2J shows schematically that the two coils C1 and C2 may be        connected in parallel with one another. Coil C2 is shown in        dashed lines.    -   FIG. 2N shows that an etched module antenna (MA2) may be formed        on the contact side of the module tape MT underneath the contact        pads CP, in addition to a module antenna (MA) on the opposite        side of the module tape.

U.S. Ser. No. 14/281,876 also discloses techniques for forming a planarantenna (PA) using laser etching, including one or both (if there aretwo) of the module antennas. For example,

-   -   FIG. 3A illustrates an antenna module (AM) comprising a        single-sided module tape having an electrically-conductive        cladding layer (CL) on one side (the face-down side) thereof.        The cladding layer CL may be etched in any suitable manner, such        as laser ablated, to create an antenna structure AS comprising a        number of electrically-conductive tracks separated by spaces,        result in a planar (flat) spiral antenna structure AS having at        least one long, continuous track comprising several turns,        separated by spaces, and having two ends for connecting to an        RFID chip CM. An electrically-conductive foil layer (FL, or        CFL), such as a layer comprising copper, may be laminated with        an adhesive (insulation) layer to the top surface of the module        tape MT. The copper foil layer CFL may be processed (etched or        otherwise patterned) to form an array of 6 or 8 contact pads        (CP) for the antenna module AM, on the face-up side of the        antenna module AM.    -   FIG. 3B illustrates an antenna module comprising a single-sided        module tape MT 302 having a copper cladding layer CCL on one        side (the face-up side). The copper cladding layer CCL may be        used to form contact pads (CP) of a contact pad array. A copper        foil layer CFL having a thickness of approximately 35 μm may        patterned in any suitable manner, such as by etching, more        particularly by laser etching, to have tracks (separated by        spaces) of an antenna structure AS, and may subsequently be        laminated (joined) to the bottom (as viewed) surface of the        module tape MT.    -   other examples of forming antenna structures, as well as        techniques and materials associated therewith, are disclosed        therein.        Chip Carrier Tape (CCT) with Module Antenna (MA) and Coupling        Frame (CF)

Some examples of module tapes (MT, also referred to as chip carriertapes CCT) having module antennas (MA) (also referred to as antennastructures AS or planar antennas PA) and coupling frames (CF) will nowbe described. RFID chips (IC, CM) may be mounted to the chip carriertapes (CCT) and connected with the module antennas (MA) or antennastructures (AS). The products described herein may operate in a purelycontactless mode (ISO 14443 or NFC/ISO 15693), without requiring contactpads (CP) for operating in a contact mode (ISO 7816). The module antenna(MA) may be a planar antenna (PA) which is a laser-etched structure(LES) or a chemically-etched structure (CES) having tracks (actually,one long track) separated by spaces, as described above, and may have(for example) 7 turns (or tracks).

Generally, a capacitive coupling enhanced (CCE) transponder chip module(TCM) may comprise:

-   -   a module tape (MT) or chip carrier tape (CCT) having a face-up        side and a face-down side;    -   an area for mounting an RFID chip (IC, CM) on the face-down side        of the module tape (MT); and    -   a module antenna (MA) disposed on the face-down side of the        module tape (MT);    -   and may be characterized in that:    -   a metal layer (ML) is disposed on at least one side of the        module tape (MT) and is formed as an open loop coupling frame        (CF) having two ends, an inner edge (IE) and an outer edge (OE),        and a slit (S) extending from an opening (OP) for the        transponder chip module (TCM), which may be defined by an inner        edge (IE) of the coupling frame (CF), to the outer edge (OE)        thereof.

The module antenna (MA) may be a planar antenna (PA) which may be achemically-etched structure (CES) or a laser-etched structure (LES)having a number of turns (tracks) separated by spaces, and two endsconnected with terminals (LA, LB) of the RFID chip (IC, CM). There maybe two module antennas (MA-1, MA-2), one of which may be disposed on theface-up side of the module tape (MT). A given single module antenna (MA)may have a tap (such as a center tap), and may be considered to be (andfunction as) two antenna structures (AS) connected in series with oneanother. A capacitor (cap) may be connected with the module antenna (MA)and/or with the RFID chip (CM, IC). The capacitor may be mountedadjacent to the RFID chip, IC or wired into the circuit somewhere else.

The coupling frame (CF) may be disposed on either the face-up side orface-down side of the module tape (MT). There may be two couplingframes, one disposed on the face-up side of the module tape (MT) theother disposed on the face-down side of the module tape (MT).

-   -   The coupling frame (CF) may be disposed around the module        antenna (MA) on the same side of the module tape (MT), with its        opening surrounding the module antenna (MA) and closely adjacent        thereto.    -   The coupling frame (CF) may be disposed on the opposite side of        the module tape (MT) from the module antenna (MA), with its        opening aligned with the module antenna (MA) on the other side        of the module tape (MT). If the opening is smaller than the        module antenna (MA), the coupling frame (CF) may overlap the        module antenna (MA).    -   The coupling frame (CF) may be asymmetric, may extend only a few        millimeters beyond the module antenna (MA) on one side thereof,        and may extend a few centimeters beyond the module antenna (MA)        on an opposite side thereof.    -   The coupling frame (CF) may have a geometry, as determined (or        defined) by the shape of its outer edge (OE), such as        elliptical, which is different that the geometry of the        transponder chip module (TCM, typically rectangular) in the        capacitive coupling enhanced (CCE) transponder chip module        (TCM). The geometry of the inner edge (IE) of the coupling frame        (CF) may be substantially the same as the geometry of the        transponder chip module (TCM, typically rectangular).

The transponder chip module (TCM) may comprise a conductive plating line(PL) extending through the slit (S) and connecting with the planarantenna (PA) and bond pads (BP) for facilitating selectively plating theplanar antenna (PA) and bond pads (BP). The planar antenna (PA) and bondpads (BP) can be plated with nickel and gold, while the coupling frame(CF) remains blank copper or brass (not plated). This is an example ofselective plating, such as may have been described in U.S. 62/039,562filed 20 Aug. 2014 and U.S. 62/048,373 filed 10 Sep. 2014.

The chip carrier tape (CCT) may be a 35 mm tape, either single- ordouble-sided (having a metal layer (ML) on either one or both sides).The antenna structure(s) can be on one side or on both sides. The RFIDchip can be mounted and bonded on the coupling frame or on an areabeside the antenna. The chip can have an input capacitance of 17 or 69pF which may influence the number of turns in the planar antenna. Wirebonds between the RFID chip (CM, IC) and the bond pads (BP) may passover the antenna tracks (in the manner of a connection bridge (CBR)),for example to connect an outer end of the planar antenna (PA) with aterminal (LA or LB) on the RFID chip.

The planar antenna (PA) (or antenna structure AS) and coupling frame(CF) may be formed by etching (either laser or chemical) the metal layer(ML). An area of the metal layer (ML) which is interior to (inside theinner edge IE of) the planar antenna (PA) may be completely removed(bulk removal), left in place, or etched to have a number of isolatedstructures, or to have another coupling frame. See FIG. 5A (bulkremoval) and FIG. 5B (isolated structures, segmenting remaining metalinside of the antenna structure/module antenna).

The planar antenna (PA) (or antenna structure AS) may comprise anelongated track having an overall length of approximately 494 mm (11turns), in the form of a rectangular spiral having tracks (traces)separated by spaces. The track width may approximately 100 μm or less,including less than 75 μm and approximately 50 μm, and may be variedalong the length of the antenna structure (AS). The spacing (or gap)between adjacent tracks (traces) may be less than 100 μm, including lessthan 75 μm, less than 50 μm, and approximately 25 μm, or less (such asafter plating) and may be varied along the length of the antennastructure (AS). The planar antenna (PA) (may comprise 10-18 turns, suchas 11 turns, and the resulting transponder chip module (TCM) may bereadable over a distance of at least 35 mm (3.5 cm), resonatingtypically at 14.2 MHz. A capacitor may be disposed in the transponderchip module (TCM) and connected with the planar antenna (PA).

Some Embodiments

Some embodiments of capacitive-coupling enhanced (CCE) transponder chipmodules (TCM) will now be described, and may utilize any of the conceptsdescribed above. These transponder chip modules (TCM) may operate solelyin a contactless mode, rather than being dual interface modules havingcontact pads.

FIGS. 4A and 4B are diagrams showing a capacitive coupling enhancedtransponder chip module (CCE-TCM, 400) comprising:

-   -   a module tape (MT, 410);    -   an RFID chip (IC, 404) disposed on the module tape (MT);    -   an etched planar antenna (PA, 402) disposed on the module tape        (MT); and    -   a coupling frame (CF, 424) disposed on the module tape (MT),        closely adjacent to the module antenna (MA), having an opening        (OP, 405) aligned (such as concentric) with the module antenna        (MA) and a slit (S, 426) extending from the opening (OP) to an        outer edge (OE) 425 of the coupling frame (CF) so that the        coupling frame (CF) is an open loop. There may be a small gap        between the inner edge (IE) of the coupling frame (CF) and an        outer turn of the module antenna (MA).

The RFID chip (IC) and module antenna (MA, PA) constitute a transponderchip module (TCM) 401. The transponder chip module (TCM) 401 may alsocomprise a substrate for supporting the RFIC chip (IC) and the moduleantenna (MA), which may be an epoxy-glass module tape (MT). The opening(OP) of the coupling frame (CF) may be defined by an inner edge (IE) 423thereof, and the slit (S) may be considered to extend from the inneredge (IE) to the outer edge (OE) of the coupling frame (CF).

The RFID chip (IC) is shown on the same side of the module tape (MT) asthe planar antenna (PA) which, may be either the face-up or face-downside of the module tape (MT). In this contactless-only, single interfaceembodiment, it is ambiguous which side is face-up and which side isface-down, since there are no contact pads (CP) defining which is theface-up side. Nevertheless, the concept of an electrically “open loop”coupling frame (CF) disposed closely adjacent to and surrounding themodule antenna (MA)—whether the coupling frame (CF) is on the same or onan opposite side of the module tape (MT) as/from the module antenna(MA)—may be applied to dual-interface (DI) transponder chip modules(TCM) also having contact pads (CP) for a contact interface, as shown inmany of the examples presented herein.

By incorporating in or adding an open-loop coupling frame (CF) to thetransponder chip module (TCM), coupling between the resulting capacitivecoupling enhanced—transponder chip module (CCE-TCM) and an externalreader (FIG. 1; “contactless reader”) may be improved, includingincreasing activation distance and read/write distance. The improvementmay be sufficient that the capacitive coupling enhanced—transponder chipmodule (CCE-TCM) may operate independently, without requiring a boosterantenna (BA) or the like which are found in smart cards. The capacitivecoupling enhanced—transponder chip module (CCE-TCM) may have a largerform factor than a conventional transponder chip module (TCM), and maybe incorporated into RFID devices other than smart cards, such aswristband devices (discussed hereinbelow), key fobs, devices with USB(universal serial bus) interfaces, and the like, having various formfactors.

U.S. Ser. No. 14/465,815 filed 21 Aug. 2014 discloses (FIG. 7B therein)incorporating a secondary coupling frame (SCF) in the transponder chipmodule (TCM) to enhance coupling between the laser-etched antennastructure (LES) of the transponder chip module (TCM) with the couplingframe (CF) in the card body (CB). To further improve the proximity ofthe laser-etched antenna (LES) to the coupling frame (CF), a metal rim(“rim”) surrounding the laser etched antenna (LES) on the transponderchip module (TCM) may be electrically connected to the coupling frame(CF) using conductive glue, solder, welding, etc. The separationdistance from the rim to the antenna can be the width of the laserwidth, less than 25 μm. The metal rim may be considered to be asecondary coupling frame (SCF), and should be open loop having a slit(S) between its two ends.

FIG. 5A is a plan view of an implementation of a transponder chip module(TCM) 500 having the planar antenna (PA) 502 disposed around the RFIDchip (IC) 504 and the coupling frame (CF) 524 disposed around the planarantenna (PA), showing the various components (elements) in greaterdetail than in the diagrams of FIGS. 4 and 4A. The planar antenna (PA)is disposed in an opening (OP) 505 in the coupling frame (CF). A slit(S) 526 extends from the opening (OP) to an outer edge (OE) 525 of thecoupling frame (CF).

The coupling frame (CF) may be formed from a conductive metal layer (ML)on the module tape (MT) or chip carrier tape (CCT) 510. The module tape(MT) may be a standard 35 mm tape, with sprocket holes (sh), as shown. Aconductive plating line (PL) 522 may extend from external to (outsideof) the coupling frame (CF), through the slit (S) to the planar antenna(PA) for purposes of plating the etched planar antenna (PA). The portionof the module tape (MT) having the sprocket holes (sh) and the portionof the plating line (PL) which is external to the coupling frame (CF)will eventually be excised—they are for manufacturing purposes—and maynot appear in the final transponder chip module (TCM) or interim product(TCM without IC).

In FIG. 5A, much (or all) of the metal layer (ML) on the module tape(MT) which is inside of the planar antenna (PA) may be removed, by bulkremoval. This, however, is time consuming FIG. 5B shows that the portionof the metal layer (ML) 506 which is inside of the planar antenna (PA)may be segmented to have several isolated conductive features, such asthe several rectangular features shown.

Coupling Frame by Embedding Wire

US 20140091149 discloses that a booster antenna BA may generallycomprise a relatively large winding which may be referred to as a cardantenna CA component (or portion) having a number of turns disposed in aperipheral area of the card body CB, and a relatively small coupler coil(or coupler antenna) CC component (or portion) having a number of turnsdisposed at a coupling area of the card body CB corresponding to theantenna module AM. The card antenna CA and coupler coil CC may comprisewire mounted to (embedded in) the card body CB using an ultrasonic toolcomprising a sonotrode and a capillary. See, for example U.S. Pat. No.6,698,089 and U.S. Pat. No. 6,233,818. The wire may be non-insulated,insulated, or self-bonding wire, having an exemplary diameter in therange of approximately 50-112 μm.

The coupling frames (CF) disclosed herein may be formed by embeddingwire in a substrate or layer thereof, whether it is a layer of a cardbody (CB), or the module tape (MT) itself. Any process (deposition,printing, etc.) resulting in an electrically-conductive layer may beused to form the coupling frame (CF). The embedded wire may meanderaround the surface of the substrate.

FIGS. 6A and 6B are diagrams (plan view) of a smartcard (SC) having atransponder chip module (TCM) and a coupling frame (CF) formed byembedding wire (EW) in a card body (CB). It may be noted that,

-   -   a portion of the wire-embedded coupling frame (CF) extends        around the periphery of the card body (CB), to provide maximum        coverage when the smart card (SC) is being scanned by a reader.    -   unlike a booster antenna (BA) which may have two free ends, the        ends of the wire-embedded coupling frame (CF) are connected with        one another (“connect ends”)    -   unlike the coupler coil (CC) of a booster antenna (BA), which        has a number of windings completely encircling (surrounding) an        area corresponding to the antenna module (AM), the wire-embedded        coupling frame (CF) only partially encircles (surrounds) the        transponder chip module (TCM). Each have an opening (OP) for the        transponder chip module (TCM).    -   In both examples, the coupling frame (CF) has a slit (S), and        may be considered to be “open loop”, with respect to the        transponder chip module (TCM), in that the coupling frame (CF)        does not completely surround the transponder chip module (TCM)        at the opening (OP).    -   In both examples, the transponder chip module (TCM) is shown        ready to be disposed in the opening (OP). A card body (CB) with        a coupling frame (CF), and a recess for receiving a transponder        chip module (TCM) may be considered to be an “interim” product.    -   In FIG. 6A, a small slit (S) is shown, as has been described for        other, “solid” coupling frames (CF) disclosed herein. The        slit (S) extends from the opening (OP), which may be considered        to be the inner edge (IE) of the coupling frame (CF) to an outer        edge (OE) of the coupling frame (CF).    -   In FIG. 6B, a larger slit (S) is shown, and the opening portion        of the coupling frame (CF) is adjacent only three of the four        sides of the transponder chip module (TCM). The large slit (S)        extends from the opening to an inner edge (IE) of the coupling        frame (CF).

The technique of wire-embedding a coupling frame (CF) may include thewire meandering, including back and forth, across the surface of thecard body (CB), rather than only around the periphery thereof.Nevertheless, it should substantially encircle (except for the slit S),and be closely adjacent to the transponder chip module (TCM).

The technique of wire-embedding a coupling frame (CF) may be applied toa module tape (MT) of a transponder chip module (TCM) rather than to thecard body (CB) of a smart card (SC) to provide a capacitive couplingenhanced transponder chip module (CCE-TCM). In a transponder chip module(TCM), this technique of having a “skeletal” (non-continuous, across itsoverall surface) coupling frame (CF) may be implemented by etching aconductive layer (CL), rather than be embedding wire. Some embodimentsof transponder devices (TD) are disclosed hereinbelow (FIGS. 7, 8) whichmay utilize embedded wire antenna structures (AS).

FIG. 6C shows a transponder chip module (TCM) positioned to be insertedin a module opening (MO) of an upper layer (UL) of a card body (CB), acoupling frame (CF) with coupler coil (CC) disposed below the upperlayer (UL), and a lower layer (LL) disposed below the coupling frame(CF) with coupler coil (CC).

The coupler coil (CC) may be in the form of a flat, rectangular spiral,having two ends. Some variations may include:

-   -   the coupler coil (CC) may be left unconnected, or floating (both        of its ends being “free ends”)    -   the two ends of the coupler coil (CC) may be connected with one        another, such as via a resistive load (or a jumper)    -   one of the two ends of the coupler coil (CC) may be connected        with the coupling frame (CF) in the card body (CB)

As best viewed in FIG. 6D, when the coupling frame (CF) is disposed in alayer of the card body (CB), it may be not be substantially coplanarwith the transponder chip module (TCM), but rather may be offsettherefrom by intervening layers (including, for example, adhesive) andthere may be a space of approximately 100-200 μm between the bottom ofthe transponder chip module (TCM), particularly its planar antenna (PA),and the plane of the coupling frame (CF). However, the coupler coil (CC)and planar antenna (PA) of the transponder chip module (TCM) may couplevery well.

In some embodiments of a coupling frame (CF) having a module opening(MO) for receiving the transponder chip module (TC) in the couplingframe (CF), the coupling frame (CF) may be substantially coplanar withthe planar antenna (PA) of the transponder chip module (TCM), however agap between the module antenna (MA) may be a few hundred microns. Insome embodiments of a coupling frame (CF) with coupler coil (CC),although there may be a space of approximately 100-200 μm between thebottom of the transponder chip module (TCM), there may be a dielectricinsulation gap of only approximately only 25-50 μm between the inneredge of the opening (OP) in the coupling frame (CF) and the outer track(turn) of the coupler coil (CC). A coupling frame (CF) with a couplercoil (CC) may exhibit better performance than a coupling frame (CF)without a coupler coil (CC).

The coupling frame (CF) with coupler coil (CC) may be etched from a foilwhile it is supported on a dielectric backing layer. The coupler coil(CC) can be approximately the same size and shape as the module antenna(MA) in the transponder chip module (TCM). The coupler coil (CC) can beelongated, such as starting at the position of the transponder chipmodule (TCM) and extending across the top half of the card body (CB).

FIG. 6E shows a card body (CB) of a smart card (SC) comprising acoupling frame (CF) having a slit (S) and also having one or morecoupler coils (CC) formed therein.

FIG. 6F shows a module tape (MT) of a capacitive coupling enhanced (CCE)transponder chip module (TCM) comprising a coupling frame (CF) having aslit (S) and also having one or more coupler coils (CC) formed therein.

Wearable Devices

Wearable devices are activity trackers, wireless-enabled devices thatmeasure data such as the number of steps walked, quality of sleep, andother personal metrics. They are usually in the form of wristbands,similar in size to a watch. A transponder for micropayment or accesscontrol can be integrated into the wristband. The transponder can be inthe form of an ID-000 (GSM SIM card) having dimensions of 15×25 mm. Amini-UICC SIM (12 mm×15 mm) has a dimension similar to that of an 8contact transponder chip module. Some of the techniques disclosed hereinmay be applicable to wearable devices.

FIG. 7 illustrates, generally an embodiment of a transponder device(TD), which may be referred to as an RFID device, and which may beincorporated into wearable items, such as wristbands. The transponderdevice (TD) may operate solely with a contactless interface, without acontact interface (and without contact pads CP). The transponder device(TD) may generally comprise (i) an RFID chip (IC) on a carrier substrate(CS), and (ii) an antenna structure (AS) functioning as a module antenna(MA) disposed on a separate (from the carrier substrate CS) devicesubstrate (DS). The carrier substrate (CS) with the RFID chip (IC) maybe joined to the device substrate (DS) with the antenna structure (AS)to form the overall transponder device (TD). Optionally, a couplingframe (CF) may be included, on the device substrate (DS), disposedaround and closely adjacent the antenna structure (AS) on the samedevice substrate (DS), in the manner of coupling frames (CF) forcapacitive coupling enhanced transponder chip modules (CCE-TCM)discussed hereinabove. The antenna structure (AS) may be an etchedplanar antenna (PA) or it may be a wire-embedded antenna, either ofwhich may have two ends connecting with terminals (such as LA, LB) ofthe RFID chip (IC). Optionally, a capacitor (CAP) may be incorporatedinto the transponder device (TD), connected with the antenna structure(AS) or with the terminals (such as LA, LB) of the RFID chip. Theresulting transponder device (TD) may perform the function of atransponder chip module (TCM), but with a much larger, elongated formfactor.

The transponder device (TD) 700 may comprise:

-   -   an RFID chip (IC) 702 disposed on a carrier substrate (CS) 704        which may be a leadframe carrier or any other suitable carrier;        -   the RFID chip (IC) may operate solely in a contactless mode;    -   an antenna structure (AS) 710 disposed on a device substrate        (DS) 712 and having two ends for connecting with the RFID chip        (IC) either directly, or via the carrier substrate (CS);        -   the device substrate (DS) may comprise a synthetic material            suitable for embedding wire to form the antenna structure            (AS). This is shown in FIG. 7. The wire-embedded antenna            structure may extend around the periphery of the device            substrate (DS) for a number of turns, and may have two ends            710 a and 710 b for connecting with terminals of the RFID            chip (IC) or associated contact pads on the carrier            substrate (CS);        -   alternatively, the device substrate (DS) may comprise a            single-sided epoxy-glass tape having a conductive metal            layer (ML) on a surface thereof which may be etched to form            the antenna structure (AS). The etched antenna structure            (AS) may be similar to the planar antennas (PA) described            hereinabove, having a number of tracks (traces) separated by            spaces, and may be chemically-etched or laser-etched.            Separate wire bridges (not shown) may connect ends of an            etched antenna structure (AS) on the device substrate (DS)            with terminals of the RFID chip (IC) or associated contact            pads on the carrier substrate (CS);        -   the device substrate (DS) may be provided with a window            opening (WO) 714 for accepting the carrier substrate (CS)            with RFID chip (IC);    -   optionally, a coupling frame (CF) 720 may be disposed on the        device substrate (DS), closely adjacent to and surrounding the        antenna structure (AS), except for a slit (S) 726 extending from        an opening (for the antenna structure) in the coupling frame        (CF) to an outer edge thereof, in the manner described        hereinabove for coupling frames (CF) in transponder chip modules        (TCM);        -   in the case of an etched antenna structure (AS), the            coupling frame (CF) may be etched from the same conductive            metal layer (CL, ML) as the antenna structure (AS);    -   optionally, a capacitor (CAP) 718 may be incorporated into the        transponder device (TD), such as by connecting it across the        antenna terminals (LA, LB) of the RFID chip (IC), or by        connecting it in series with the antenna structure (AS) on the        device substrate (DS).

The device substrate (DS) may be elongated, and may measureapproximately 7 mm wide by 48 mm long, or 8 mm wide by 40 mm long, forexample.

The device substrate (DS) may comprise a soft, embeddable material suchas PVC (polyvinyl chloride). Alternatively, other materials may be used,and the device substrate (DS) may have a coating (such as a gluecoating) to accept wire-embedding.

The antenna structure (AS), which may be referred to as a substrateantenna (SA), may be embedded into the device substrate (DS) usingultrasonic embedding techniques such as are disclosed in U.S. Pat. No.6,698,089 and U.S. Pat. No. 6,233,818 and U.S. Pat. No. 6,088,230. Thesubstrate antenna (SA) may comprise 4 or 5 turns around the periphery ofthe device substrate (DS). Track spacing of the module antenna (MA) maybe varied to control capacitance.

The carrier substrate (CS), which may be a leadframe carrier (LC), withRFID chip (IC) mounted thereon, may be referred to as a “chip module”730. The chip module does not have its own antenna (module antenna MA),and therefore does not function as a transponder (it has no contact padsfor a contact interface, and no module antenna for a contactless) andmay therefore not be referred a transponder chip module (TCM). With theantenna structure (AS) connected to the RFID chip (IC), the overalltransponder device (TD) may function as a transponder chip module (TCM).

The figure shows the chip module (carrier substrate CS and RFID chip IC)being mounted from behind to the back or bottom surface of the devicesubstrate (DS) so that its contact pads are exposed for being connectedto by the ends of the antenna structure (AS) (or intermediate wirebridges). To this end, the device substrate (DS) may be provided with anopening (WO) 714 for receiving the carrier substrate (CS) and RFID chip(IC). The size of the opening (OP) may be greater than the size of thechip module (CS and IC) so that the chip module may “float” when thedevice substrate (DS) is flexed.

Alternatively, the carrier substrate (CS) may be disposed on the frontside of the device substrate (DS) and connected in a suitable mannerwith the antenna structure (AS). The antenna structure (AS) connectedwith an RFID chip (IC) constitutes a transponder chip module (TCM), theantenna structure functioning as a module antenna (MA) for thetransponder chip module (TCM).

If etched, the antenna structure (AS) may comprise 4 or 5 turns (tracks,traces) separated by spaces, in the manner of various module antenna(MA) described above. An embedded wire antenna structure (AS) maycomprise 7-10 turns around the periphery of the device substrate (DS).These numbers (of turns) are intended to be exemplary.

The coupling frame (CF), having a slit (S), and two opposed ends, may bedisposed around the periphery of the device substrate (DS), on eitherside of the device substrate (DS), such as

-   -   (i) disposed on the same side of the device substrate (DS)        around and closely adjacent to an antenna structure (AS), such        as shown in FIG. 3M (with regard to PA-1 and CF), or    -   (ii) disposed on the opposite side of the device substrate (DS)        so that it an inner portion of the coupling frame (CF) may        overlap (or underlie) an outer portion of the antenna structure        (AS), such as shown in FIG. 3K (with respect to CF and PA).

With the optional coupling frame (CF), the transponder device (TD)constitutes a capacitive coupling enhanced (CCE) transponder chip module(TCM) capable of contactless communication (with an external reader).

Transponder Chip Modules (TCM) Connected with an External Antenna (ANT)

FIGS. 8A, 8B illustrate, generally an embodiment of a transponder device(TD), which may be referred to as an RFID device, and which may beincorporated into wearable items, such as wristbands. The transponderdevice (TD) may operate solely with a contactless interface, without acontact interface (and without contact pads CP). The transponder device(TD) may generally comprise (i) an RFID chip (IC) on a carrier substrate(CS) with a module antenna (MA), and (ii) an additional antennastructure (AS) disposed on a separate (from the carrier substrate CS)device substrate (DS). The carrier substrate (CS) with the RFID chip(IC) and module antenna (MA) may be joined to the device substrate (DS)with the additional antenna structure (AS) to form the overalltransponder device (TD). Optionally, a coupling frame (CF) may beincluded, on the device substrate (DS), disposed around and closelyadjacent the additional antenna structure (AS) on the same devicesubstrate (DS), in the manner of coupling frames (CF) for capacitivecoupling enhanced transponder chip modules (CCE-TCM) discussedhereinabove. The additional antenna structure (AS) may be an etchedplanar antenna (PA) or it may be a wire-embedded antenna, either ofwhich may have two ends connecting with terminals (such as LA, LB) ofthe RFID chip (IC). Optionally, a capacitor (CAP) may be incorporatedinto the transponder device (TD), In this embodiment, the RFID chip (IC)on a carrier substrate (CS) with a module antenna (MA) constitutes atransponder chip module (TCM), in and of itself. With the additionaldevice substrate (DS) and antenna structure (AS), it may be consideredto be an “inductively enhanced” (by virtue of the additional antennastructure AS) transponder chip module (IE-TCM) and, with a couplingframe (CF) on the device substrate it may be considered to be aninductively-enhanced, capacitive coupling enhanced transponder chipmodule (E-CCE-TCM), The resulting transponder device (TD) may performthe function of a transponder chip module (TCM), but with a much larger,elongated form factor.

The transponder device (TD) 800 may comprise:

-   -   an RFID chip (IC) 802 and a module antenna 806 disposed on a        carrier substrate (CS) 804 which may be a leadframe carrier or        any other suitable carrier. Together, these elements (an IC        connected with a MA) may be considered to be a transponder chip        module (TCM) 830 capable of functioning on its own;        -   the RFID chip (IC) may operate solely in a contactless mode;    -   an antenna structure (AS) 810 disposed on a device substrate        (DS) 812 and having two ends for connecting with the RFID chip        (IC) either directly, or via the carrier substrate (CS), or with        the module antenna (MA);        -   the device substrate (DS) may comprise a synthetic material            suitable for embedding wire to form the antenna structure            (AS). This is shown in FIG. 8. The wire-embedded antenna            structure may extend around the periphery of the device            substrate (DS) for a number of turns, and may have two ends            810 a and 810 b for connecting with terminals of the RFID            chip (IC) or associated contact pads on the carrier            substrate (CS);        -   alternatively, the device substrate (DS) may comprise a            single-sided or double-sided epoxy-glass tape having a            conductive metal layer (ML) on a surface thereof which may            be etched to form the additional antenna structure (AS). The            etched additional antenna structure (AS) may be similar to            the planar antennas (PA) described hereinabove, having a            number of tracks (traces) separated by spaces, and may be            chemically-etched or laser-etched. Separate wire bridges            (not shown) may connect ends of an etched additional antenna            structure (AS) on the device substrate (DS) with terminals            of the RFID chip (IC) or associated contact pads on the            carrier substrate (CS);        -   the device substrate (DS) may be provided with a window            opening (WO) 814 for accepting the carrier substrate (CS)            with RFID chip (IC) and module antenna (MA);    -   optionally, a coupling frame (CF, not shown, compare 720) may be        disposed on the device substrate (DS), closely adjacent to and        surrounding the additional antenna structure (AS), except for a        slit (S, not shown, compare 726) extending from an opening (for        the additional antenna structure) in the coupling frame (CF) to        an outer edge thereof, in the manner described hereinabove for        coupling frames (CF) in transponder chip modules (TCM);        -   in the case of an etched additional antenna structure (AS),            the coupling frame (CF) may be etched from the same            conductive metal layer (CL, ML) as the additional antenna            structure (AS);    -   optionally, a capacitor (CAP, not shown, compare 718) may be        incorporated into the transponder device (TD), such as by        connecting it across the antenna terminals (LA, LB) of the RFID        chip (IC), or by connecting it in series with the additional        antenna structure on the device substrate (DS).

The device substrate (DS) may be elongated, and may measureapproximately 7 mm wide by 48 mm long, or 8 mm wide by 40 mm long, forexample.

The device substrate (DS) may comprise a soft, embeddable material suchas PVC (polyvinyl chloride). Alternatively, other materials may be used,and the device substrate (DS) may have a coating (such as a gluecoating) to accept wire-embedding.

The additional antenna structure (AS), which may be referred to as asubstrate antenna (SA), may be embedded into the device substrate (DS)using ultrasonic embedding techniques such as are disclosed in U.S. Pat.No. 6,698,089 and U.S. Pat. No. 6,233,818 and U.S. Pat. No. 6,088,230.The substrate antenna (SA) may comprise 4 or 5 turns around theperiphery of the device substrate (DS), and may be connected in seriesor parallel with the module antenna (MA) 806 on the transponder chipmodule (TCM) 830. The module antenna (MA) may be a etched planar antenna(PA) such as described for other embodiments of transponder chip modules(TCM). Track spacing of the module antenna (MA) may be varied to controlcapacitance. The figure shows the substrate antenna (SA) 810 disposed onthe front surface of the device substrate (DS) 812, and ends of thesubstrate antenna (SA) 810 connected to two rectangular connection padson the carrier substrate (CS) 804 of the transponder chip module (TCM)830.

The device substrate (DS) 812 with antenna structure (AS) or substrateantenna (SA) 810 may be considered to be an “interim product” ready toreceive, at a later date, a transponder chip module 830, at which timethe antenna structure (AS) may be connected with the transponder chipmodule (TCM).

The carrier substrate (CS), which may be a leadframe carrier (LC), withRFID chip (IC) and module antenna (MA) mounted thereon, may be referredto as a “chip module”. The chip module has its own antenna (moduleantenna MA), and therefore may function as a transponder and maytherefore be referred a “transponder chip module” 830. The transponderchip module (TCM) 830 may function alone as an RFID transponder, it hasan RFID chip (IC) and an antenna (module antenna MA). Its capability isenhanced by the external additional antenna structure (AS) on the devicesubstrate (DS).

The figure shows the transponder chip module (carrier substrate CS, RFIDchip IC and module antenna MA) being mounted from behind to the back orbottom surface of the device substrate (DS) so that its contact pads areexposed for being connected to by the ends of the additional antennastructure (AS) (or intermediate wire bridges). To this end, the devicesubstrate (DS) may be provided with an opening (WO) 714 for receivingthe transponder chip module (TCM, or carrier substrate (CS) with RFIDchip (IC and module antenna (MA)). The size of the opening (OP) may begreater than the size of the chip module (CS and IC) so that the chipmodule may “float” when the device substrate (DS) is flexed.

Alternatively, the transponder chip module 830 may be disposed on thefront side of the device substrate (DS) and connected in a suitablemanner with the additional antenna structure (AS). The additionalantenna structure (AS) connected with the transponder chip module 830constitutes an enhanced transponder chip module (E-TCM), the additionalantenna structure functioning in a manner similar to an antenna embeddedin the card body (CB) of a smart card (SC) and connected with an RFIDchip. See, e.g., U.S. Pat. No. 7,980,477 (Dual Interface Inlays). Exceptin this example, the additional antenna structure is connected with afully-contactlessly-functional transponder chip module, rather than withmerely an RFID chip.

If etched, the additional antenna structure (AS) may comprise 4 or 5turns (tracks, traces) separated by spaces, in the manner of variousmodule antenna (MA) described above. An embedded wire a additionalantenna structure (AS) may comprise 7-10 turns around the periphery ofthe device substrate (DS). These numbers (of turns) are intended to beexemplary.

A coupling frame (CF), if any (none shown) may be disposed on the devicesubstrate (DS) in the manner described with respect to the transponderdevice 700 of FIG. 7. The coupling frame (CF) may be disposed around theperiphery of the device substrate (DS), on either side of the devicesubstrate (DS), such as

-   -   (i) disposed on the same side of the device substrate (DS)        around and closely adjacent to the additional antenna structure        (AS), or    -   (ii) disposed on the opposite side of the device substrate (DS)        so that it an inner portion of the coupling frame (CF) may        overlap (or underlie) an outer portion of the additional antenna        structure (AS).

With the optional coupling frame (CF), the transponder device (TD)constitutes an capacitive coupling enhanced (CCE) inductively enhanced(by virtue of the additional antenna structure) transponder chip module(TCM) capable of contactless communication (with an external reader).

In summary, a wire antenna (SA) is embedded on an elongated devicesubstrate (DS) and connected to the transponder chip module (TCM) whichhas an RFID chip (IC) and its own module antenna (MA). A coupling frame(CF) may be disposed around the exterior of or within the interior ofthe substrate antenna (SA), and closely spaced therefrom. A couplingframe (CF) may be substituted for the substrate antenna (SA), if closespacing with the module antenna (MA) can be maintained.

A capacitor (not shown) may be incorporated into the transponder chipmodule (TCM) and connected with the module antenna (MA). The capacitor,which may be a silicon capacitor, may be connected in parallel with themodule antenna (MA), or it may be inserted between the module antenna(MA) and the substrate antenna (SA). One end of the capacitor may beconnected to the RFID chip (IC), and the other may be connected to a tapof a dual antenna.

An Etched, Planar Module Antenna (MA, PA)

Planar antennas (PA) which are etched, particularly laser-etched, from aconductive layer (CL) on a module tape (MT) or other substrate (such asthe device substrates DS), and functioning as a module antenna (MA) orother antenna structure (AS) have been mentioned hereinabove. Also, withregard to FIGS. 5A and 5B, the issue of “bulk removal” of metal insideof the module antenna (MA) versus segmenting the remaining metal insideof the module antenna (MA) to have many isolated conductive structuresinstead of one large metal area was briefly introduced. Attention willnow be directed to segmenting the conductive metal layer (ML, CL)remaining inside a laser-etched module antenna (MA), as an example ofany laser-etched antenna structure (AS). A conductive layer (CL)comprising copper will be described, as exemplary of etching anyconductive material for a module antenna (MA).

In laser ablating single- or double-sided glass epoxy tape to expose anantenna structure (AS), there is inevitably a bulk area of copper whichneeds to be removed. This bulk removal of copper from the surface of theglass epoxy tape takes up valuable laser time. Inasmuch as the remainingcopper is a conductive surface in the middle of the antenna, such as in(but not limited to) the case of the wristband antenna (FIGS. 7, 8), theremaining copper may significantly affect the resonance frequency andpower delivery to the RFID chip (IC). In the case of a dual interfacetransponder chip module the same applies, there is an area in the middleof the laser etched module antenna (the position of the die) which needsto be removed. On the face-up (contact pad) side of the module tape (MT)there is also a large conductive (copper) area in the middle of thecontact pad array (CPA), which is usually left in place and contiguouswith the C5 contact pad.

It may be advantageous not to bulk remove the copper from the center ofthe module antenna (MA) (or, from the center of the contact pad arrayCPA), but rather to segment the remaining copper surface by creatingslits or tracks in the copper by laser-etching, resulting in severalsmaller isolated conductive areas rather than one large conductive area.This may also be characterized as rendering the entire large area lessconductive overall, and may be referred to as “profiling” the coppersurface. Some examples will be presented.

In the examples that follow, an antenna structure (AS) 900 is shown, ona module tape (MT) 902 or other suitable substrate. The antennastructure (AS) may be an etched planar antenna (PA), particularly alaser-etched antenna structure (AS), etched from a conductive layer (CL)904 on the module tape (MT), suitable to be incorporated into atransponder chip module (TCM) as an example of any transponder device orRFID device as the module antenna (MA) or other antenna structure (AS)thereof. Such an antenna structure (AS) may comprise a plurality oftracks (traces, as mentioned before, actually one long spiraling track)separated by spaces, disposed in a rectangular spiral pattern around aperiphery of the module tape (MT). Examples of segmenting a portion ofthe metal conductive layer (CL) 904 remaining in an area inside of(interior to) the module antenna (MA) are shown.

FIG. 9A shows an antenna structure (AS) 900 on a module tape (MT) 902wherein the conductive layer 904 remaining at the interior area of theantenna structure (within the turns of the antenna structure) is asingle large, conductive structure. This constitutes a “no segmentation”baseline.

FIG. 9B shows an antenna structure (AS) 900 on a module tape (MT) 902wherein the conductive layer 904 remaining at the interior area of theantenna structure (AS) has been segmented with “low” segmentation—inthis example, one slit (SL) 906 extending in a first direction(horizontal, as viewed) across the remaining conductive layer, and nineslits (SL) 906 extending in another (such as perpendicular) direction(vertical, as viewed) across the remaining conductive layer, resultingin twenty (2×10, a plurality of) smaller isolated (from one another)conductive structures 904 b. The slits (SL) may be evenly or unevenlyspaced, and the resulting smaller isolated conductive structures may bethe same size as one another, or different sizes than one another.

The slits (SL) described herein may be formed by laser etching, in amanner similar to how the slit (S) in the coupling frame (CF) may bemade, but serve a different purpose (these figures are directed to themodule antenna, not the coupling frame).

FIG. 9C shows an antenna structure (AS) 900 on a module tape (MT) 902wherein the conductive layer 904 remaining at the interior area of theantenna structure (AS) has been segmented with “medium” segmentation—inthis example, two slits (SL) 906 extending in a first direction(horizontal, as viewed) across the remaining conductive layer, and tenslits 906 extending in another (such as perpendicular) direction(vertical, as viewed) across the remaining conductive layer, resultingin thirty-three (3×11, a plurality of) smaller isolated (from oneanother) conductive structures 904 c. The slits may be evenly orunevenly spaced, and the resulting smaller isolated conductivestructures may be the same size as one another, or different sizes thanone another.

FIG. 9D shows an antenna structure (AS) 900 on a module tape (MT) 902wherein the conductive layer 904 remaining at the interior area of theantenna structure (AS) has been segmented with “high” segmentation—inthis example, three slits 906 extending in a first direction(horizontal, as viewed) across the remaining conductive layer, andnineteen slits 906 extending in another (such as perpendicular)direction (vertical, as viewed) across the remaining conductive layer,resulting in eighty (4×20, a plurality of) smaller isolated (from oneanother) conductive structures 904 d. The slits may be evenly orunevenly spaced, and the resulting smaller isolated conductivestructures may be the same size as one another, or different sizes thanone another.

Although the actual amount of copper removed may be quite small (theslits may be less than 100 μm wide), several benefits may accrue tosegmenting the conductive layer material within a module antenna (MA),or other comparable antenna structure (AS). This may include beneficialeffects on the associated module's resonance frequency (it can beshifted), less signal attenuation due to smaller eddy currents in thesegmented embodiments, and the like. Some benefits accruing to profilingthe copper surface may include the ability to tune the resonancefrequency of the antenna circuit (the module antenna and whatever it isconnected to, such as the RFID chip, which has a characteristic inputcapacitance) by the number of slits, and resulting isolated conductiveareas which are created. This may make it possible to tune an antennastructure (AS, MA) to a specific RFID chip having a given inputcapacitance. As the input capacitance of RFID chips stemming from wafersproduced by a semiconductor foundry may vary from batch-to-batch,segmenting a conductive area remaining interior to (inside of) a moduleantenna (MA) may make it possible to tune the module antenna preciselyfor a given wafer batch or for a given chip set. Antenna structures (AS)may be tuned, without changing the antenna geometry itself.

Chip Input Capacitance

The RFID chip (IC, CM) has a characteristic input capacitance, such asat the terminals (LA, LB) connecting to the module antenna (MA). Lowcapacitance chips (input 17 pF) can be made to work with our transponderchip module and coupling frame, by increasing the number of turns from10 to 18 turns. High capacitance chips (input 69 pF) operate with thesame performance as the low capacitance chips, but with a lower numberof (such as 6-9) turns.

Pure Contactless Embodiments

As mentioned above, some of the techniques disclosed herein may beapplicable to transponder chip modules (TCM) operating solely in acontactless mode, in which case there may not be any contact pads (CP).In the absence of (and in lieu of) contact pads (CP), the transponderchip module (TCM) may be provided with isolated metal features to pullthe resonance to the frequency of interest. These isolated metalfeatures may for example be a logo or design.

Electrostatic Discharge (ESD)

ESD is a miniature lightning bolt of charge that moves between a personhandling a metal object, such as a metal card or a plastic card with ametallization layer and the contact pads of a module connected to anRFID chip, both surfaces having different potentials. It can occur onlywhen the voltage differential between the surface of the metal and thecontact pads on a chip module is sufficiently high to break down thedielectric strength of the air medium separating the two surfaces. Whena static charge moves, it becomes a current that may damage or destroygate oxide, metallization, and junctions in the RFID chip. ESD can occurin any one of many different ways: a charged person can touch (come intocontact with) or rub the chip module, a charged chip module can touch agrounded surface, a charged point of sale terminal can touch a chipmodule, or an electrostatic field can induce a voltage across adielectric sufficient to break it down.

Normally RFID chips are protected against any ESD events that mightoccur to any bond pad that is exposed to its environment. However,handling of metal cards with a contact chip module or a dual interfacechip module are subject to very high discharge voltages which can causethermal damage to the RFID chip.

Because ESD can occur only when different potentials are involved, thebest way to avoid ESD damage is to keep the RFID chip at the samepotential as its surroundings. The logical reference potential is ESDground. Therefore, in order to intercept Electrostatic Discharge (ESD)arcs from a person handling a metal card with a chip module, thefollowing measures can be undertaken:

-   -   Clamping the ground contact pad (C5) on the chip module to the        metal card body surface or to a metallization layer in a plastic        card body to protect it against ESD surges (discharges)    -   Clamping an ESD protection device such as a suppressor diode or        capacitor between the ground contact pad (C5) of the chip module        and the metal card body or to a metallization layer in a plastic        card body    -   Applying anti-static foam or static dissipative material between        the chip module and the metal card body or a metallization layer        in a plastic card body    -   Connecting (attaching) a suppressor diode or capacitor across        the slit (S) of the coupling frame (CF)

The metal frame of a card body may be connected with the ground pin(pad) C5 of the module (of course on the opposite side, and not on thecontact side), using any suitable connection technique. Alternatively, adirect connection of the metal card body and the ground pin of the chipmodule could be considered.

It is also possible to use a capacitor e.g. 100 nF instead of asuppressor diode. These ESD protection devices are very standard, andreadily available. These devices are intended to clamp all voltagesabove a certain voltage level. An anti-ESC patch (foam) may also beused, such as a milled/punched ESD plastic Seehttp://www.murtfeldt.de/produkte/kunststoffe/

Power Transfer

An important issue when dealing with passive RFID transponders is powertransfer or delivery from the external reader to the RFID chip. A smallgap between tracks (spaces between traces) for the planar antenna (PA)may be beneficial, and may best be achieved with laser etching (versuschemical etching). With laser etching, gaps of 25 μm or less (withsubsequent plating) may be achieved. Track width may also have an effecton power transfer, a narrower track width may provide for better powertransfer. (This may be because with narrower tracks, you can fit moretracks in a given area and with a given spacing.) Again, laser etchingmay provide an advantage over chemical etching, and track widths of lessthan 100 μm, including less than 75 μm, less then 50 μm andapproximately 25 μm may be achieved with laser etching. (Chemicaletching may be limited to track widths greater than 100 μm and spacinggreater than 100 μm.)

While the invention(s) has/have been described with respect to a limitednumber of embodiments, these should not be construed as limitations onthe scope of the invention(s), but rather as examples of some of theembodiments. Those skilled in the art may envision other possiblevariations, modifications, and implementations that are also within thescope of the invention(s), and claims, based on the disclosure(s) setforth herein.

The invention claimed is:
 1. A capacitive coupling enhanced (CCE)transponder chip module (TCM) comprising: a module tape (MT); an areafor mounting an RFID chip (IC) on the module tape (MT); and a moduleantenna (MA, PA) disposed on the module tape (MT); characterized by: aconductive coupling frame (CF) disposed on the module tape (MT) havingan opening (OP) defined by an inner edge (IE), an outer edge (OE) and adiscontinuity comprising a slit (S) or a non-conductive stripe (NCS)extending from the opening (OP) to the outer edge (OE); wherein theopening (OP) is disposed surrounding and closely adjacent to the moduleantenna (MA); wherein: the coupling frame (CF) is formed from aconductive layer (CL) on the module tape (MT) which is one of the (i)conductive layer used to form contact pads (CP) on the face-up side ofthe module tape (MT) and (ii) the conductive layer used to form themodule antenna on the face-down side of the module tape (MT).
 2. Thecapacitive coupling enhanced (CCE) transponder chip module (TCM) ofclaim 1, wherein: the coupling frame (CF) is disposed on the same sideof the module tape (MT) as the module antenna (MA, PA).
 3. Thecapacitive coupling enhanced (CCE) transponder chip module (TCM) ofclaim 1, wherein: the coupling frame (CF) is disposed on an oppositeside of the module tape (MT) from the module antenna (MA, PA).
 4. Thecapacitive coupling enhanced (CCE) transponder chip module (TCM) ofclaim 1, wherein: the coupling frame (CF) comprises wire (EW) embeddedin the module tape (MT).
 5. The capacitive coupling enhanced (CCE)transponder chip module (TCM) of claim 1, wherein: the module antenna(MA) comprises an etched planar antenna (PA) having a number of tracks(traces) separated by spaces; wherein: a track width is less than 100μm; and a spacing between adjacent tracks is less than 75 μm.
 6. Thecapacitive coupling enhanced (CCE) transponder chip module (TCM) ofclaim 1, wherein: the module antenna (MA) comprises two antennastructures (PA-1, PA-2).
 7. The capacitive coupling enhanced (CCE)transponder chip module (TCM) of claim 1, further comprising: acapacitor (CAP) connected with the module antenna (MA).
 8. Thecapacitive coupling enhanced (CCE) transponder chip module (TCM) ofclaim 1, wherein: there are two coupling frames (CF-1, CF-2), onedisposed on a face-up side of the module tape (MT) the other disposed ona face-down side of the module tape (MT).
 9. The capacitive couplingenhanced (CCE) transponder chip module (TCM) of claim 1, wherein: thecoupling frame (CF) is disposed around the module antenna (MA) with itsopening (OP) surrounding the module antenna (MA) and closely adjacentthereto.
 10. The capacitive coupling enhanced (CCE) transponder chipmodule (TCM) of claim 1, wherein: the coupling frame (CF) overlaps atleast a portion of the module antenna (MA).
 11. The capacitive couplingenhanced (CCE) transponder chip module (TCM) of claim 1, wherein: thecoupling frame (CF) extends a few millimeters beyond the module antenna(MA) on one side thereof, and extends a few centimeters beyond themodule antenna (MA) on an opposite side thereof.
 12. The capacitivecoupling enhanced (CCE) transponder chip module (TCM) of claim 1,wherein: the coupling frame (CF) has a geometry defined by a shape ofits outer edge (OE) which is different than a geometry of thetransponder chip module (TCM).
 13. The capacitive coupling enhanced(CCE) transponder chip module (TCM) of claim 1, further comprising: aplating line (PL) extending from outside of the coupling frame (CF),through the slit (S) in the coupling frame (CF) to the module antenna(MA).
 14. The capacitive coupling enhanced (CCE) transponder chip module(TCM) of claim 1, further comprising: conductive traces (CT) extendingbetween at least some contact pads (CP) and connection bridges (CBR) ofthe contact pad array (CPA).
 15. A capacitive coupling enhancedtransponder chip module (CCE-TCM, 400) comprising: a module tape (MT);an RFID chip (IC) disposed on the module tape (MT); an etched moduleantenna (MA) disposed on the module tape (MT); and a coupling frame (CF)disposed on the module tape (MT), closely adjacent to the module antenna(MA), having an opening (OP) aligned with the module antenna (MA) and aslit (S) extending from the opening (OP) to an outer edge (OE) of thecoupling frame (CF) so that the coupling frame (CF) is an open loop;wherein: the coupling frame (CF) is formed from a conductive layer (CL)on the module tape (MT) which is one of the (i) conductive layer used toform contact pads (CP) on the face-up side of the module tape (MT) and(ii) the conductive layer used to form the module antenna on theface-down side of the module tape (MT).
 16. The capacitive couplingenhanced transponder chip module (CCE-TCM) of claim 15, furthercomprising: contact pads (CP) so that the capacitive coupling enhancedtransponder chip module (CCE-TCM) can function with dual interfaces(contactless and contact).